Can I claim GST on purchases made before I registered for GST?

Yes, you can claim GST on purchases up to 6 months before your registration date, but only in your first GST return. You must have proper tax invoices in your company name, expenses must relate to taxable supplies you will make after registration, and for goods you must still hold them. Claim in Box 7 and indicate Yes in Box 12 for pre-registration claims.

How long does it take to get a GST refund in Singapore?

Standard GST refunds take 4-6 weeks. Large refunds may take 6-12 weeks or longer as IRAS reviews them more carefully. IRAS may send queries before releasing refund, and you must respond promptly or the refund stays frozen. If no refund after 8 weeks, check myTax Portal for updates or contact IRAS.

Can I claim GST on meals and entertainment expenses?

Generally no, unless you meet specific conditions. Entertainment expenses are disallowed except when provided to customers in the course of business with proper documentation of attendees and business purpose, and the expense is reasonable. Staff meals, team dinners, and directors meals without customers present are not claimable. Documentation is critical as IRAS will disallow claims without records on audit.

Can I claim GST on my company car in Singapore?

Generally no. Motor cars are disallowed under GST regulations. Exceptions where you can claim include licensed taxis, driving school vehicles, car dealers holding cars as stock, and car rental companies. Goods vehicles like vans and lorries designed for carrying goods allow input tax claims if for business use. Motorcycles are not classified as motor cars so input tax is claimable for business use.

What are the GST filing deadlines in Singapore?

GST filing deadlines in Singapore are one month after each quarter ends: Q1 January to March due 30 April, Q2 April to June due 31 July, Q3 July to September due 31 October, Q4 October to December due 31 January of the following year. Payment must be made by the same deadline as filing. Late filing incurs penalties starting at $200 for first offense.

Do I need to file GST if I have no business activity in a quarter?

Yes, you must file a nil return by entering $0 in all boxes. Not filing because you had no activity still counts as late filing with a minimum penalty of $200. Filing the nil return takes only 5 minutes and is required by IRAS regardless of business activity level.

GST Filing in Singapore: Step-by-Step Guide to F5 Form [2025]

You've hit $1 million in revenue. Congratulations. Now you're GST-registered and IRAS expects you to file Form F5 every quarter. Miss the deadline? $200 first offense, $1,000 second offense, up to $5,000 if you keep missing it. Mess up the calculation? IRAS query. Get it wrong repeatedly? Audit. Fun times.

Most Singapore SMEs find the F5 form confusing. Seven main boxes, each requiring specific calculations. Output tax, input tax, standard-rated supplies, zero-rated supplies, claimable versus non-claimable expenses. Get one number wrong and IRAS sends a query letter asking you to explain.

After years at KPMG and Deloitte working on statutory audits, I've reviewed hundreds of GST returns. The same mistakes appear repeatedly: wrong timing of supplies, incorrect input tax claims, mixing up standard-rated and zero-rated sales, claiming GST on disallowed expenses. Most of these errors are preventable with proper understanding of the F5 form.

Here's the reality: Filing GST takes 2-3 hours per quarter if your records are organised monthly. If they're a mess? Plan for 5-10 hours of sorting receipts, reconciling bank statements, and figuring out which expenses qualify for input tax claims. First time filing? Add another 2-3 hours just learning what each box means.

This guide walks you through the entire GST filing process. You'll learn what each box on the F5 form means, how to calculate output and input tax correctly, which expenses you can claim GST on, and how to avoid the mistakes that trigger IRAS attention. I'll also show you the actual steps to file via myTax Portal, so you know exactly what to expect.

Who needs this guide: Every GST-registered business filing quarterly returns. Whether you're doing it yourself or just want to understand what your accountant is doing, you'll know the complete process by the end.

GST Filing Basics: What You're Actually Filing
Before You Start: What You Need Ready
Understanding the F5 Form: Complete Box Breakdown
Step-by-Step: Filing F5 via myTax Portal
Standard-Rated Supplies: The Complexities
Input Tax Claims: Conditions and Restrictions
Special Cases and Adjustments
Additional Complexities and Edge Cases
After Filing: What Happens Next
DIY vs Professional Help: The Real Cost
Frequently Asked Questions
Quick Recap: GST Filing Checklist
Making Your Decision: What's Next

GST Filing Basics: What You're Actually Filing

Before diving into the F5 form, understand what GST filing actually involves.

What is GST filing:

GST filing is your quarterly declaration to IRAS showing:

How much GST you collected from customers (output tax)
How much GST you paid to suppliers (input tax)
The difference: what you owe IRAS or what IRAS owes you

Think of it as reconciliation. Every quarter, you're telling IRAS: "I collected $5,000 in GST from sales, paid $3,000 in GST on purchases, so here's the net $2,000 I owe you."

Who must file:

All GST-registered businesses (no exceptions)
Even if you have no business activity that quarter, you still file (just report zero)

Filing frequency:

Most businesses file quarterly. Your accounting periods:

Q1: 1 January to 31 March
Q2: 1 April to 30 June
Q3: 1 July to 30 September
Q4: 1 October to 31 December

Some businesses file monthly (if approved by IRAS, usually large companies). Some file annually (if approved, usually for very small turnover). But standard is quarterly for most SMEs.

When to file:

You have one month after the quarter ends:

Q1 (Jan-Mar): Due 30 April
Q2 (Apr-Jun): Due 31 July
Q3 (Jul-Sep): Due 31 October
Q4 (Oct-Dec): Due 31 January (following year)

File even one day late? $200 penalty minimum. Already filed late once before? Penalty jumps to $1,000. Keep missing? Up to $5,000 per filing. We covered this in detail in our complete guide to Singapore filing deadlines and penalties.

What happens after filing:

If you owe GST (output tax exceeds input tax):

Pay by the same deadline as filing
Payment methods: GIRO, internet banking, or via myTax Portal
Late payment triggers additional 5% penalty if unpaid more than 60 days

If IRAS owes you (input tax exceeds output tax):

IRAS processes refund within 4-6 weeks
Refund paid directly to your bank account
Large refunds may trigger queries (IRAS wants to verify)

The form you're filing:

Form F5 (GST F5 Return). It's an electronic form on the myTax Portal with multiple boxes requiring specific information. Each box serves a distinct purpose. Get one wrong and you're explaining to IRAS why the numbers don't match their expectations.

Understanding what you're filing helps prevent errors. You're not just filling boxes randomly. You're declaring your complete GST position for the quarter.

Before You Start: What You Need Ready

Filing F5 requires organised records. Missing documents mean you're guessing numbers, which IRAS doesn't appreciate.

Here's what you absolutely need before logging into myTax Portal.

Documents You Must Have

Sales records (for output tax calculation):

All sales invoices issued during the quarter
Each invoice showing GST charged separately
Credit notes issued (reduces your output tax)
Deposits or advance payments received
Bank statements showing payments received

Purchase records (for input tax claims):

All supplier invoices received during the quarter
Each invoice must be proper tax invoice (supplier's GST registration number visible)
Import permits (if you imported goods)
Credit notes received from suppliers
Bank statements showing payments made

Why proper tax invoices matter:

You can't claim input tax without proper tax invoices. A proper tax invoice must show:

Supplier's name, address, and GST registration number
Your company name and address
Invoice date and number
Description of goods/services
Total amount and GST amount separately stated

Receipt from coffee shop showing "$10.90 including GST"? Not a proper tax invoice but it is ok if meets the requirements of simplified tax invoices. Supplier invoice showing "$10,000 + $900 GST, GST Reg No: M12345678X"? Proper tax invoice. Can claim the $900.

Information You Need to Calculate

For Box 1 (Standard-rated supplies):

Total value of sales where you charged 9% GST
Value EXCLUDING GST (if invoice shows $10,900 including GST, you declare $10,000)

For Box 2 (Zero-rated supplies):

International sales to non-Singapore customers
Goods exported (need export documentation)
International transport/freight services

For Box 3 (Exempt supplies):

Financial services provided
Residential property rental or sale
Most SMEs will have $0 here

For Box 5 (Output tax):

Total GST collected from customers
Usually Box 1 × 9%

For Box 6 (Input tax):

Total GST paid on claimable business expenses
Not all expenses qualify (we'll cover restrictions later)

For Box 7 (Net GST):

Box 5 minus Box 6
Positive number = you pay IRAS
Negative number = IRAS refunds you

Software vs Manual Calculation

If using Xero, QuickBooks, or other accounting software:

Your software should auto-calculate most boxes if:

You've set up GST tracking correctly
You've coded all transactions properly (standard-rated, zero-rated, exempt)
You've reconciled your bank accounts
You've marked which expenses are claimable for input tax

Time required: 1-2 hours (mostly reviewing and verifying the auto-calculated figures)

If using Excel or manual records:

You calculate everything yourself:

Sum all standard-rated sales
Sum all zero-rated sales
Calculate output tax (standard-rated × 9%)
Sum all claimable input tax from supplier invoices
Calculate net GST

Time required: 3-5 hours (depending on transaction volume)

If you have no organised records:

You're reconstructing the quarter from bank statements, loose receipts, and memory. You'll need to:

Go through every bank transaction
Match to invoices (if you can find them)
Determine which were sales vs expenses
Figure out which expenses had GST
Hope you're not missing anything

Time required: 8-15 hours (possibly more)

Reality check: If you're in this situation, hire an accountant urgently. The time you'll spend plus the risk of errors costs more than professional help.

Cut-Off Procedures

End of quarter cut-off matters.

Example problem:

You issued invoice on 31 March: $10,000 + $900 GST
Customer paid on 5 April
Which quarter do you declare this in?

Answer: Q1 (when invoice issued), not Q2 (when payment received). GST accounting follows tax point rules, usually based on invoice date.

But deposits complicate this:

Customer paid $5,000 deposit in February
Final invoice $20,000 in April
Q1 filing: Declare $5,000 deposit (output tax = $450)
Q2 filing: Declare remaining $15,000 (output tax = $1,350)

Getting timing wrong is a common error that triggers IRAS queries.

Checklist Before You Start Filing

Go through this checklist. If you can't tick everything, stop and organise your records first:

[ ] All sales invoices for the quarter (including deposits received)
[ ] All purchase invoices with proper tax invoice format
[ ] Bank reconciliation completed
[ ] Credit notes identified and separated
[ ] Standard-rated vs zero-rated sales identified
[ ] Claimable vs non-claimable input tax identified
[ ] Any adjustments from previous quarters noted
[ ] Calculator and patience ready

Time estimate based on your records:

Monthly bookkeeping done throughout quarter: 1-2 hours filing
Quarterly bookkeeping catch-up: 3-5 hours
No bookkeeping (reconstructing from scratch): 8-15 hours
First time filing: Add 2-3 hours learning curve

Most businesses that struggle with GST filing have a record-keeping problem, not a filing problem. Fix your bookkeeping process and filing becomes straightforward.

Our monthly bookkeeping service keeps your records organised year-round, making quarterly GST filing a simple 30-minute review and submit process instead of a multi-day ordeal.

Understanding the F5 Form: Complete Box Breakdown

The GST F5 Return has fifteen boxes (some with sub-sections). The myTax Portal auto-calculates certain boxes, but you need to understand what goes where.

Here's what each box means, based on official IRAS guidance.

The Main Boxes (1-8)

Box 1: Total Value of Standard-Rated Supplies

This is the value of supplies where you charged 9% GST.

Enter the value EXCLUDING GST.

Example: If you sold goods for $100 and charged $9 GST, enter $100 here (not $109).

What to include:

Sale of goods to customers
Services provided in Singapore
Digital services supplied by overseas vendor (via reverse charge)
Lease of commercial properties or hotel rooms
Management fees, commissions, maintenance fees
Supplies to staff (canteen takings, vending machine sales)
Deemed supplies (goods taken for private use, gifts over $200)
Sale of business assets (factory building, business equipment)
Reimbursement of expenses from third party
Reverse charge on imported services (declare here, then claim back in Box 7)

What to deduct:

Credit notes issued (refunds given to customers)

What NOT to include:

Out-of-scope supplies (goods shipped from overseas to overseas)
GST wrongfully collected before registration date
Zero-rated supplies (Box 2)
Exempt supplies (Box 3)

Box 2: Total Value of Zero-Rated Supplies

Supplies taxed at 0% GST (still taxable, so you can claim input tax).

What to include:

Goods exported out of Singapore (need export permit)
International services listed in Section 21(3) of GST Act
International transport and freight

What to deduct:

Credit notes issued for zero-rated supplies

Most SMEs: $0 unless exporting or providing international services.

Box 3: Total Value of Exempt Supplies

Supplies with no GST, and you can't claim related input tax.

What to include:

Sale and lease of residential properties
Financial services (interest, insurance, securities, net foreign exchange gains/losses)
Sale of investment precious metals
Supply of digital payment tokens (from 1 Jan 2020)

Most SMEs: $0 unless in finance, property, or precious metals.

Box 4: Total Value of All Supplies

Auto-calculated: Box 1 + Box 2 + Box 3

This is your total supplies for the quarter. System calculates automatically.

Box 5: Total Value of Taxable Purchases

Value of purchases where you can claim input tax.

Enter the value EXCLUDING GST.

Example: If you bought goods for $100 with $9 GST, enter $100 here (not $109).

What to include:

Standard-rated purchases from GST-registered suppliers
Imports of goods for business
Zero-rated purchases (international freight, air tickets)
Reverse charge on imported services and low-value goods (from 1 Jan 2023)
Pre-registration purchases (first return only, up to 6 months before registration)

What to deduct:

Credit notes received (supplier refunds, discounts)
Value of purchases you must repay input tax on (if unpaid after 12 months from due date)

What NOT to include:

Motor car costs and running expenses (with specific exceptions)
Club subscription fees
Medical expenses for staff (unless specific conditions met)
Medical insurance premiums (unless specific conditions met)
Benefits for family members/relatives of staff
Betting, gambling, games of chance
Private purchases (not for business)
Exempt purchases (residential property, bank charges, investment precious metals)
Purchases from non-GST-registered businesses
Wages and salaries

IRAS warning: Don't calculate Box 5 by reverse-engineering Box 7. Track them separately.

Box 6: Output Tax Due

GST you charged on standard-rated supplies.

Example: Sold goods for $100, charged $9 GST → Enter $100 in Box 1, enter $9 in Box 6.

What to include:

GST charged on standard-rated supplies (Box 1 items)
GST on reverse charge (imported services/low-value goods)
GST on recovered bad debts (if previously claimed relief)

What to deduct:

GST on credit notes issued

IRAS warning: Don't calculate Box 6 by using Box 1 × 9% due to rounding differences. Track output tax separately.

Box 7: Input Tax and Refunds Claimed

GST you're claiming back.

Example: Bought goods for $100 with $9 GST → Enter $100 in Box 5, enter $9 in Box 7.

What to include:

GST on standard-rated purchases (Box 5 items)
GST on imports (from import permits)
GST on reverse charge (imported services/low-value goods - declare in Box 6, claim back here)
Tourist Refund Scheme refunds made to tourists
Bad debt relief (if conditions satisfied)
Reverse charge adjustments (unpaid overseas suppliers after 12 months)
Pre-registration GST (first return only, if eligible)

What to deduct:

GST on credit notes received
Repayment of input tax (if didn't pay supplier within 12 months)

What NOT to include (same disallowed list as Box 5):

GST on motor cars
GST on club subscriptions
GST on medical expenses (with exceptions)
GST on family benefits
GST on betting/gambling
GST on private purchases
Purchases from non-GST-registered suppliers

IRAS warning: Don't calculate Box 7 from Box 5. Track input tax separately.

Box 8: Net GST to be Paid to or Claimed from IRAS

Auto-calculated: Box 6 minus Box 7

Positive = You owe IRAS
Negative = IRAS owes you refund
Less than $5 either way = No payment/refund, not carried forward

Additional Boxes (9-17)

Box 9: Total Value of Goods Imported Under MES/A3PL/Other Approved Schemes

Only for businesses approved under:

Major Exporter Scheme (MES)
Approved Third Party Logistics (A3PL) Scheme
Other approved schemes

Enter value of imports under these schemes (GST suspended, no input tax to claim).

Most SMEs: Not applicable.

Box 10: Did You Claim GST You Refunded to Tourists?

If you operate Tourist Refund Scheme and claimed TRS refunds in Box 7:

Select "Yes"
State amount claimed

Most SMEs: Select "No".

Box 11: Did You Make Bad Debt Relief Claims and/or Reverse Charge Refund Claims?

If you claimed in Box 7:

Bad debt relief, OR
Reverse charge adjustments (unpaid overseas suppliers after 12 months)

Select "Yes" and state amount.

Most SMEs: Select "No" unless making these specific claims.

Box 12: Did You Make Pre-Registration Claims?

Only appears on your first GST return.

If you claimed pre-registration GST in Box 7:

Select "Yes"
State GST amount claimed

Disappears after first return.

Box 13: Revenue

Your total revenue for the quarter from profit & loss accounts.

Include:

Main income from services
Sale of goods
Other operating income (gross sales/turnover)

Exclude:

Income from sale of fixed assets
Grants received
Gross receipts collected on behalf of others

Can use estimates if exact figures not available. This is based on your accounting treatment, may differ from Box 4 (which is GST-based).

Box 14: Did You Import Services and/or Low-Value Goods Subject to GST Under Reverse Charge?

For "RC Businesses" (not entitled to full input tax claims):

Banks and financial institutions
Investment-holding companies
Property developers
Charities providing free/subsidised services

If you're an RC Business and imported services/low-value goods under reverse charge:

Select "Yes"
State value (same amount included in Box 1)

Most SMEs making only taxable supplies: Not applicable.

Box 15: Did You Operate an Electronic Marketplace to Supply Remote Services on Behalf of Third-Party Suppliers?

For overseas/local electronic marketplace operators supplying digital services (and non-digital services from 1 Jan 2023) on behalf of platform suppliers:

Select "Yes"
Include value (same amount in Box 1)

Most SMEs: Not applicable.

Box 16: Are You a Redeliverer or Electronic Marketplace Operator Supplying Imported Low-Value Goods on Behalf of Third-Party Suppliers?

From 1 Jan 2023, if you're a redeliverer/electronic marketplace regarded as supplier of low-value goods:

Select "Yes"
Include value (same amount in Box 1)

Most SMEs: Not applicable.

Box 17: Did You Supply Imported Low-Value Goods Subject to GST?

From 1 Jan 2023, if you're a supplier of low-value goods:

Select "Yes"
Include value (same amount in Box 1)

Most SMEs: Not applicable.

Boxes 18-21: Import GST Deferment Scheme (IGDS) Section

Only available for businesses approved under IGDS.

Most SMEs: These boxes won't appear on your form.

Summary: Which Boxes Most SMEs Use

Always use:

Box 1 (Standard-rated supplies)
Box 4 (Auto-calculated total)
Box 5 (Taxable purchases)
Box 6 (Output tax - auto or manual)
Box 7 (Input tax)
Box 8 (Net GST - auto-calculated)
Box 13 (Revenue)

Sometimes use:

Box 2 (If exporting/international services)
Box 11 (If claiming bad debt relief)
Box 12 (First return only, if pre-registration claims)

Rarely use:

Boxes 3, 9, 10, 14-17 (Special situations)

Step-by-Step: Filing F5 via myTax Portal

Now for the actual filing process.

Before You Start

Requirements:

CorpPass (companies) or Singpass (sole proprietors)
All calculated figures ready
All figures converted to Singapore dollars
30-60 minutes

IRAS reminder: Even if no transactions, you must file nil return (enter $0 in all boxes).

Access myTax Portal

Go to mytax.iras.gov.sg
Click "Login"
Select CorpPass or Singpass
Authenticate
Navigate to "GST" section
Select "File GST Return (F5)"

Select Accounting Period

Choose the correct quarter:

Q1: 01/01/2025 to 31/03/2025 (due 30 Apr)
Q2: 01/04/2025 to 30/06/2025 (due 31 Jul)
Q3: 01/07/2025 to 30/09/2025 (due 31 Oct)
Q4: 01/10/2025 to 31/12/2025 (due 31 Jan)

Verify the deadline shown. If past deadline, you're already facing penalties.

Fill the Main Boxes

Box 1: Enter value of standard-rated supplies (excluding GST)

All sales where you charged 9% GST
Refer to Section 3 for what to include/exclude

Box 2: Enter value of zero-rated supplies

Exports and international services
Most SMEs: $0

Box 3: Enter value of exempt supplies

Financial services, residential property
Most SMEs: $0

Box 4: Auto-calculated (Box 1 + 2 + 3)

Verify it looks correct

Box 5: Enter value of taxable purchases (excluding GST)

All purchases where you can claim input tax
Refer to Section 3 for what to include/exclude
Don't include disallowed expenses

Box 6: Enter output tax

GST you charged customers
Usually Box 1 × 9%, but track separately
Don't calculate from Box 1 due to rounding

Box 7: Enter input tax

GST you're claiming back
Only on claimable purchases
Don't calculate from Box 5 due to rounding

Box 8: Auto-calculated (Box 6 - Box 7)

Positive = You pay IRAS
Negative = IRAS refunds you
Less than $5 = No action needed

Fill Additional Boxes

Box 9: Imports under special schemes

Most SMEs: Leave blank

Box 10: TRS claims

Select "Yes" only if claimed in Box 7
Most SMEs: "No"

Box 11: Bad debt/reverse charge claims

Select "Yes" only if claimed in Box 7
State amount

Box 12: Pre-registration claims (first return only)

Select "Yes" if claimed in Box 7
This box disappears after first filing

Box 13: Revenue

Enter from profit & loss accounts
Can estimate if exact figure unavailable
Include operating income, exclude grants/asset sales

Boxes 14-17: Digital services/reverse charge/low-value goods

Most SMEs: "No" to all
Only applicable for specific business types

Review Before Submitting

Check for common errors:

Included GST in Box 1 or Box 5 (should be excluding GST)
Wrong quarter selected
Forgot to convert foreign currency to SGD
Missing a zero ($1,000 vs $10,000)
Box 6 roughly equals Box 1 × 9%?
Box 7 looks reasonable for your purchases?

Submit

Tick declaration: "I declare that the information given in this return is true and correct"
Click "Submit"
Save confirmation:
- Submission reference number
- Amount payable/refundable
- Payment deadline

Print or download confirmation PDF.

Make Payment (If Box 8 Positive)

Must pay by same deadline as filing.

Payment options:

GIRO: Auto-deduction (if set up)
Internet banking: Pay via your bank's IRAS payment function
myTax Portal: Credit card or online banking via portal

Late payment = 5% penalty if unpaid more than 60 days after deadline.

After Submission

If you owe GST:

Verify payment processed
Keep confirmation

If IRAS owes you:

Refund within 4-6 weeks
Large refunds may take longer (IRAS reviews)
Paid to registered bank account

IRAS may query:

If figures look unusual
If refund is large
If filed very late
Respond within their deadline

Done. Mark your calendar for next quarter's deadline.

Common Filing Errors IRAS Sees

Mistake 1: Including GST in Box 1

Wrong: Sold for $109 (including GST), entered $109
Correct: Sold for $109 (including GST), enter $100

Mistake 2: Including GST in Box 5

Wrong: Bought for $109 (including GST), entered $109
Correct: Bought for $109 (including GST), enter $100

Mistake 3: Calculating Box 6 from Box 1

Don't do: Box 1 × 9% = Box 6
Instead: Track output tax separately

Mistake 4: Calculating Box 7 from Box 5

Don't do: Box 5 × 9% = Box 7
Instead: Track input tax separately

Mistake 5: Including disallowed expenses in Box 5 and Box 7

Motor cars, club subscriptions, medical expenses
Refer to Section 3 for complete disallowed list

Mistake 6: Wrong quarter selected

Filing for Q1 but accidentally selected Q2
Can't easily undo, requires amendment

Mistake 7: Not converting foreign currency

All figures must be in SGD
Use appropriate exchange rate

For comprehensive coverage of common GST mistakes and how to avoid them, see our detailed guide: Common GST Mistakes Singapore Businesses Make.

Standard-Rated Supplies: The Complexities

Box 1 seems simple: "Enter value of standard-rated supplies." But the complexity comes from determining WHEN to declare the supply and HOW to value it in tricky situations.

Here's where most businesses get it wrong.

Time of Supply Rules: When to Declare

The biggest question: Which quarter do I declare this sale in?

Basic rule: The earlier of:

Invoice date
Payment received date

But this gets complicated fast.

Scenario 1: Invoice and Payment in Different Quarters

Invoice issued: 28 March (Q1)
Payment received: 5 April (Q2)
Declare in: Q1 (invoice date is earlier)

Scenario 2: Payment Before Invoice

Customer paid deposit: 15 February (Q1)
Invoice issued: 10 April (Q2)
Declare in: Q1 for the deposit amount, Q2 for the balance

Scenario 3: Progress Billing

Construction project billed in stages:

Stage 1 invoice: $50,000 on 10 Jan
Stage 2 invoice: $30,000 on 15 Mar
Stage 3 invoice: $40,000 on 5 Apr
Final invoice: $20,000 on 10 Jun

Declare:

Q1: $50,000 + $30,000 = $80,000
Q2: $40,000 + $20,000 = $60,000

Each invoice creates a time of supply. You can't wait until project completion to declare everything.

Scenario 4: Retention Sums

You invoice $100,000, customer pays $90,000 immediately and retains $10,000 pending defect rectification.

Declare in Q1: Full $100,000 (based on invoice date)

Not when the retention is finally released. The time of supply is when you invoice, regardless of whether customer has paid everything.

Scenario 5: Continuous Supply of Services

Monthly retainer: $5,000/month

Option A: Issue monthly invoices

Declare $5,000 each month as invoiced

Option B: One invoice covering 6 months

Declare full $30,000 in quarter invoice issued

Option C: Quarterly invoices

Declare $15,000 each quarter

The frequency of invoicing determines when you declare. If you want to spread GST liability across quarters, invoice quarterly (or monthly).

Deposits and Advance Payments

Deposits trigger GST immediately, even if no invoice issued yet.

Scenario 1: Refundable vs Non-Refundable Deposits

Customer pays $10,000 deposit for custom furniture:

Non-refundable deposit:

Time of supply: When deposit received
Declare in that quarter
Even if no invoice yet

Refundable deposit:

No time of supply until converted to payment
Don't declare until either invoiced or customer confirms order

Most business deposits are non-refundable once work begins, so declare immediately.

Scenario 2: Deposits Spanning Multiple Quarters

Deposit received: $20,000 on 25 March
Final invoice: $80,000 on 15 May
Total contract: $100,000

Q1 filing: Declare $20,000 (deposit) Q2 filing: Declare $80,000 (balance)

Don't wait until final invoice to declare the deposit. GST on $20,000 is due in Q1.

Scenario 3: Multiple Deposits

First deposit: $10,000 on 10 Jan
Second deposit: $15,000 on 20 Feb
Third deposit: $5,000 on 5 Apr
Final invoice: $70,000 on 10 Jun

Q1 filing: $10,000 + $15,000 = $25,000 Q2 filing: $5,000 + $70,000 = $75,000

Each deposit is a separate time of supply.

Mixed Supplies: Standard-Rated and Zero-Rated

Single transaction with both standard-rated and zero-rated elements.

Scenario 1: Goods Sold Locally + Exported

Invoice to customer:

100 units delivered in Singapore: $50,000 (standard-rated)
50 units exported: $25,000 (zero-rated)
Total: $75,000 + $4,500 GST = $79,500

Filing:

Box 1: $50,000
Box 2: $25,000
Box 6: $4,500

Must split the invoice correctly. Can't just dump everything in Box 1.

Scenario 2: Service with Local and International Components

Marketing campaign:

Singapore market research: $30,000 (standard-rated)
Overseas market research: $20,000 (zero-rated, provided to overseas client)
Invoice total: $50,000 + $2,700 GST

Filing:

Box 1: $30,000
Box 2: $20,000
Box 6: $2,700

Need proper apportionment. Document how you split local vs international.

Scenario 3: Ambiguous Mixed Supply

IT consulting project for overseas client:

Work done in Singapore office: 60% of project
Work done at client's overseas office: 40% of project
Total fee: $100,000

Question: Is the 60% standard-rated (performed in Singapore) or is the entire supply zero-rated (supplied to overseas business)?

Answer depends on:

Where customer is located (Singapore or overseas?)
Whether service qualifies as "international service" under Section 21(3)

This requires careful analysis. Get it wrong and IRAS will query.

Partially Exempt Businesses

If you make both taxable and exempt supplies, Box 1 calculations get complicated.

Example business: Property developer

Commercial property sales: Standard-rated
Residential property sales: Exempt

Why this matters for Box 1: You must track standard-rated sales separately. Can't just lump all property sales together.

Input tax complication: Can't claim 100% of input tax. Must apportion based on ratio of taxable vs exempt supplies.

Example:

Standard-rated sales: $2M
Exempt sales: $8M
Total: $10M
Input tax to claim: Only 20% ($2M / $10M)

This gets complex fast. If your business has exempt supplies, you likely need professional help with apportionment calculations.

Vouchers, Discounts, and Rebates

Scenario 1: Early Payment Discount

Invoice: $10,000 + $900 GST = $10,900, with terms "2% discount if paid within 7 days"

Customer pays early: $10,680 (after $218 discount)

Original filing (when invoiced):

Box 1: $10,000
Box 6: $900

Adjustment (when discount taken): Issue credit note for $200 + $18 GST

Next quarter filing:

Deduct $200 from Box 1
Deduct $18 from Box 6

Or just accept you over-declared by $18. Small amounts aren't worth adjusting.

Scenario 2: Volume Rebate

Customer buys throughout year. If purchases exceed $100,000, you give 5% rebate at year-end.

Q1-Q3: Declare sales at full price Q4: Issue credit note for rebate amount, reduce Box 1 and Box 6

Don't try to predict the rebate. Declare at full price until rebate is confirmed.

Scenario 3: Promotional Vouchers

You sell $100 vouchers for $80 (20% off promotion).

When selling voucher:

No GST declared yet (voucher is just a payment instrument)

When customer redeems voucher:

Declare based on goods/services value, not voucher face value
If customer redeems $100 voucher for $100 of goods: Declare $100 supply

Vouchers create timing complexity. GST is on redemption, not sale of voucher.

Sales to connected companies must be at "open market value."

Scenario: Selling to Your Own Subsidiary

Your company sells goods to 100% owned subsidiary:

Your cost: $50,000
Normal selling price: $80,000
Invoiced to subsidiary: $60,000 (friendly price)

IRAS position: Should declare $80,000 (open market value), not $60,000.

Box 1: May need to declare $80,000 even though invoice shows $60,000.

IRAS can challenge related party transactions if pricing appears manipulated to reduce GST. Document why your pricing is reasonable.

Scenario: Free Supply to Related Party

You "give" goods to sister company for free.

IRAS position: This is a deemed supply. Must declare at open market value.

Can't avoid GST by calling it "free" when it's to a related party.

Deemed Supplies

Certain transactions are deemed supplies even though no invoice or payment.

Scenario 1: Goods Taken for Private Use

Director takes inventory (laptop worth $2,000) for personal use.

Deemed supply: $2,000 must be declared in Box 1.

Why: You claimed input tax when purchasing inventory. If used privately, must account for output tax.

Scenario 2: Business Gifts Over $200

You give corporate gifts to clients. Total GST incurred on gifts: $250.

Deemed supply: Must declare gift value in Box 1 and account for output tax.

Threshold: If total GST on gifts exceeds $200, becomes deemed supply.

Scenario 3: Goods Transferred Between Divisions

If you have separate divisions (not GST grouped), transferring goods between them may be deemed supply.

Complex area. Depends on how divisions are structured.

Change of Use

Goods initially for taxable supplies, later used for exempt supplies (or vice versa).

Scenario: Property Developer

Bought land intending to develop commercial property (taxable). Claimed input tax on purchase.

Later changed plan to residential development (exempt).

Requirement: Must repay portion of input tax claimed, as the land will now generate exempt supplies.

Adjustment calculation is complex, based on proportion of exempt use.

Foreign Currency Transactions

If invoice in foreign currency, must convert to SGD for Box 1.

Which exchange rate?

Use rate on invoice date (for time of supply purposes)
Or use rate on payment date if paid before invoice
Be consistent

Example:

Invoice USD $10,000 on 15 March when rate is 1.35:

SGD equivalent: $13,500
Box 1: $13,500
Box 6: $1,215 (9% of $13,500)

Customer pays on 5 April when rate is 1.38:

You receive SGD $13,800
Box 1 still: $13,500 (based on invoice date rate)
Foreign exchange gain/loss is not GST issue

Key Takeaway

Standard-rated supplies aren't just "sales where you charged GST." The complexity is in:

Timing: When to declare (invoice vs payment vs deposit)
Valuation: What value to declare (especially for related parties, mixed supplies, discounts)
Classification: Whether something is actually standard-rated or zero-rated or exempt
Apportionment: If you have exempt supplies, how to split
Deemed supplies: Recognising when you must declare even without invoice

Most businesses need professional help if they deal with:

Cross-border transactions
Related party sales
Partially exempt supplies
Complex payment structures (deposits, retention, progress billing)

Our monthly bookkeeping service includes proper GST classification and timing. We handle the complexity so you don't mis-declare and trigger IRAS queries.

Input Tax Claims: Conditions and Restrictions

Not all GST you pay is claimable. Box 7 requires careful judgment about what qualifies.

Here are the complex conditions that trip up most businesses.

The Attribution Test: Core Requirement

To claim input tax, the expense must be "attributable to taxable supplies."

Sounds simple. It's not.

What "attributable" means:

The purchase must be:

For business purposes (not private)
Related to making taxable supplies (not exempt supplies)
Incurred in the course of your business

Scenario 1: Clear Attribution

You run a consultancy (only standard-rated services). You buy laptops for staff.

Laptops used 100% for business: Input tax claimable ✓
Clear link to taxable supplies

Scenario 2: No Attribution

Same consultancy. Director buys laptop for spouse who doesn't work in business.

Not for business purposes: Input tax NOT claimable ✗
No link to taxable supplies

Scenario 3: Ambiguous Attribution

Consultancy buys high-end coffee machine for office.

Staff use it: Business purpose ✓
But does coffee-making "attribute to taxable supplies"?

IRAS position: Generally claimable if for staff welfare in business premises. But if excessively luxurious, IRAS may challenge.

The line is grey. Document business purpose clearly.

Scenario 4: Mixed Use

Director uses office laptop 80% for business, 20% for personal.

Strict interpretation: Should only claim 80% of input tax.

Practical approach: If predominantly business use (>50%), most businesses claim 100%. But you're exposed if IRAS audits.

Safer approach: Claim proportionate input tax based on actual business use percentage.

Partial Exemption: Input Tax Apportionment

If you make both taxable and exempt supplies, you can't claim 100% of input tax on overhead expenses.

Who this affects:

Banks and financial institutions (exempt financial services)
Property developers (residential = exempt, commercial = taxable)
Investment holding companies (dividends = exempt)
Mixed-use businesses

The apportionment rule:

For overhead expenses that relate to both taxable and exempt supplies:

Claimable input tax = Total input tax × (Taxable supplies / Total supplies)

Example: Property Developer

Annual supplies:

Residential sales (exempt): $8M
Commercial sales (taxable): $2M
Total: $10M

Overhead expenses (office rent, utilities, admin staff):

Total input tax: $50,000

Claimable input tax: $50,000 × ($2M / $10M) = $10,000

You lose 80% of your overhead input tax claims because 80% of your supplies are exempt.

Direct attribution saves input tax:

If an expense relates ONLY to taxable supplies, claim 100% of that input tax.

Example:

Marketing costs for commercial property: 100% claimable (directly attributable to taxable supplies)
Marketing costs for residential property: 0% claimable (directly attributable to exempt supplies)
General office overhead: Apportion using ratio

Track expenses carefully. Maximize direct attribution to taxable supplies where possible.

De minimis rule:

If exempt supplies are less than certain thresholds, you may be able to claim all input tax without apportionment. Check current IRAS rules for de minimis limits.

The 12-Month Payment Rule

Claimed input tax but didn't pay your supplier within 12 months? You must repay the input tax to IRAS.

Why this rule exists: Prevents businesses from claiming input tax on invoices they never intend to pay.

How it works:

Q1: You receive invoice from supplier: $10,000 + $900 GST

Payment due: 30 days (30 April)
You claim input tax in Q1: $900 in Box 7 ✓

12 months later (30 April following year): Still haven't paid supplier

Requirement: Must repay $900 to IRAS in your next GST return

Where to adjust:

Deduct $900 from Box 7 (reduce input tax claimed)
Or include in "repayment of input tax" section

If you later pay the supplier: Can claim the input tax again in the quarter you finally pay.

Common scenario: Dispute with supplier, invoice unpaid for over a year while negotiating.

You must repay input tax after 12 months, even if dispute is unresolved. Can claim again if you eventually pay.

Cash flow trap:

Claimed $900 input tax in Year 1
Repay $900 to IRAS in Year 2 (because still unpaid to supplier)
Finally pay supplier in Year 3, claim $900 again

The input tax claim is delayed by 2 years if you don't pay suppliers promptly.

Proper Tax Invoice Requirements

Can't claim input tax without proper tax invoice. But what counts as "proper"?

Minimum requirements:

A proper tax invoice must show:

Supplier's name, address, and GST registration number
Your company name and address
Invoice date and number
Description of goods/services
Total amount payable
GST amount charged (stated separately)

Common problems:

Problem 1: GST not shown separately

Receipt: "Total: $1,090 (including GST)"

Not a proper tax invoice
Can't claim input tax
Need invoice showing: "$1,000 + $90 GST"

Problem 2: Missing GST registration number

Invoice shows everything except supplier's GST registration number.

Not valid for input tax claim
Request corrected invoice from supplier

Problem 3: Simplified invoice from retail purchase

Coffee shop receipt: "$10.90"

This is simplified tax invoice (allowed for transactions <$1,000)
But you need to calculate GST yourself: $10.90 ÷ 1.09 = $10.00, GST = $0.90
Can claim $0.90

But some accounting software won't accept simplified invoices. Depends on your record-keeping system.

Problem 4: Invoice to different entity

Supplier invoice addressed to your related company, not your company.

Can't claim input tax (invoice not in your name)
Even if you paid it
Need invoice re-issued to correct entity

Problem 5: Lost invoice

You paid supplier, lost the invoice, supplier no longer exists.

Can't claim input tax without invoice
Bank statement alone isn't sufficient
Try to reconstruct: email records, order confirmations, alternative documentation

Digital invoices:

Email invoices, PDF invoices are acceptable IF they contain all required information.

Don't need physical paper. Digital is fine.

Motor Vehicle Restrictions: Detailed Rules

"Motor cars" are generally disallowed. But the definition of "motor car" is specific.

What's a "motor car" under Regulation 25:

A vehicle designed to carry passengers (not goods) with seating for ≤7 persons including driver.

Disallowed input tax:

Purchase of motor car
Running costs (fuel, maintenance, repairs, parking, insurance, road tax)
Hire/lease of motor car

Exceptions where input tax IS claimable:

Exception 1: Taxi

Licensed taxi used for carrying passengers for hire
Input tax 100% claimable

Exception 2: Driving school vehicle

Used solely for driving instruction by licensed driving school
Input tax 100% claimable

Exception 3: Car dealer

Cars held as stock for sale
Input tax claimable (attributed to taxable supplies)

Exception 4: Rental car company

Cars rented out to customers
Input tax claimable

Vehicles that AREN'T "motor cars" (input tax claimable):

Goods vehicles:

Vans, lorries, trucks designed primarily for carrying goods
Input tax claimable if used for business

Motorcycles:

Not a "motor car"
Input tax claimable if for business use

Buses:

Designed for >7 passengers
Not a "motor car"
Input tax claimable if for business use

Key question: Is it designed to carry passengers (car) or goods (van)?

Grey area: SUVs and MPVs

Singapore classifies by COE category:

Category A/B = Car (input tax disallowed)
Category C = Commercial vehicle (input tax allowed if for business)

A van registered as commercial vehicle: Input tax claimable The same van registered as private car: Input tax disallowed

Registration category matters, not just vehicle type.

Hire car complexities:

Company rents car for 3 months:

If for director's private use: Input tax disallowed
If for business purpose (e.g., transport clients): Still disallowed (car hire restriction applies)

Exception: If hire is essential and temporary (e.g., company van breaks down, hire replacement van): Input tax claimable

Parking charges:

Company pays season parking for director's car at office: Input tax disallowed (related to motor car)

Company pays parking for delivery van: Input tax claimable

Entertainment Restrictions: When You CAN Claim

Entertainment expenses are generally disallowed. But there are specific conditions where you CAN claim.

Default rule: Input tax on entertainment is disallowed.

Exceptions where input tax IS claimable:

Exception 1: Entertainment provided in the course of business to customers

Conditions:

Customer entertainment (not staff or own directors)
Provided in course of business (client meetings, business development)
Properly documented (who attended, business purpose)
Reasonable in relation to business conducted

Example - Claimable:

Client dinner to discuss contract: $500 + $45 GST
Attendees documented: Your director + 2 client representatives
Purpose: Negotiate terms of $500K contract
Input tax claimable: $45 ✓

Example - Not claimable:

Same dinner but only your own directors attended (no client): Disallowed ✗
Lavish dinner ($3,000) for small contract ($5,000): IRAS may challenge reasonableness

Documentation requirements:

Keep records showing:

Who attended (names, companies)
Business purpose
Relationship to business deals
Reasonableness of expense

Without documentation, IRAS will disallow on audit.

Exception 2: Entertainment as part of your business

If your business IS entertainment, input tax claimable.

Examples:

Restaurant: Food and drinks are your taxable supplies (input tax claimable)
Hotel: Meals provided to guests as part of service (input tax claimable)
Event management company: Client events are your business (input tax claimable)

IRAS scrutinises this. Claim only when clearly business-purpose entertainment with proper documentation.

Reverse Charge: Double Entry Explained

When you import services from overseas supplier (and you're an RC Business), you account for both output tax AND input tax.

Why reverse charge exists: Overseas supplier isn't GST-registered, so can't charge you GST. You self-account for it.

How it works:

You engage overseas consultant: USD $10,000 fee (no GST charged)

Your GST filing:

Box 1: Include $13,500 (converted to SGD)
Box 6: Include $1,215 (9% output tax)
Box 5: Include $13,500
Box 7: Include $1,215 (input tax claim)

Net effect: Usually zero ($1,215 output tax minus $1,215 input tax = $0)

But not always zero:

Scenario 1: RC Business (partially exempt)

If you're a bank (exempt financial services), you can't claim full input tax.

Box 6: $1,215 (output tax, must account for)
Box 7: $0 or partial (can't claim input tax on exempt supplies)
Net: You owe IRAS $1,215 (or portion thereof)

Scenario 2: Didn't pay overseas supplier within 12 months

Can claim input tax back (similar to domestic 12-month rule):

Include adjustment in Box 7
Repay the input tax since supplier unpaid

Scenario 3: Imported service for exempt supplies

Even if normally fully taxable business, if this specific imported service relates to exempt supplies, can't claim that input tax.

Example: Consultancy firm (normally taxable) engaging overseas consultant for advice on its rental property (exempt).

Still account for output tax in Box 6
But can't claim input tax in Box 7
Net: Owe IRAS $1,215

Reverse charge doesn't always net to zero. Depends on your input tax claiming entitlement.

Capital Goods Scheme: Long-Term Assets

Assets over a certain value ($1 million threshold per IRAS rules) have special input tax claiming rules.

Why it exists: Prevent claiming 100% input tax on major asset used for both taxable and exempt supplies over many years.

How it works:

Claim input tax over 5-10 years (depending on asset type) rather than immediately.

Example: Property Developer Buys Land

Land cost: $10M + $900K GST

Instead of claiming $900K in one quarter: Claim $90K per year over 10 years (if land scheme applies)

Adjustment if use changes:

Year 1-3: Used for commercial development (taxable) Year 4-10: Changed to residential (exempt)

Must repay portion of input tax claimed in years 1-3, as later use is for exempt supplies.

Calculations get complex. Definitely need professional advice if dealing with capital goods scheme.

Key Takeaway

Input tax claiming isn't just "keep the invoice and claim the GST." You must verify:

Attribution: Expense relates to taxable supplies?
Apportionment: If partially exempt, calculate claimable portion
Payment: Did you pay supplier within 12 months?
Invoice: Do you have proper tax invoice?
Restrictions: Is it motor car or entertainment (special rules)?
Reverse charge: Accounted for correctly?
Capital goods: Subject to multi-year adjustment?

Get any of these wrong and IRAS will disallow your input tax claim, plus potentially penalties for incorrect filing.

For detailed coverage of common input tax claiming mistakes, see our guide: Common GST Mistakes Singapore Businesses Make.

Our monthly bookkeeping service includes proper input tax classification and documentation. We track all conditions and restrictions so your claims are defensible on audit.

Special Cases and Adjustments

Beyond standard filing, certain situations require special treatment or adjustments to previous returns.

Bad Debt Relief: Claiming Back Output Tax

Customer didn't pay? You can claim back the GST you already paid to IRAS on that sale.

Basic concept:

You invoiced customer: $10,000 + $900 GST
You declared $900 output tax in Box 6 and paid IRAS
Customer never paid you
After meeting conditions, you can claim the $900 back in Box 7

Conditions to qualify:

1. Debt must be genuinely bad

Written off in your accounting records
Reasonable attempts made to recover
Debtor insolvent, disappeared, or uncontactable

2. Time requirement

At least 6 months since payment was due
For debts relating to supplies made before 1 Jan 2019: 12 months

3. Original output tax must have been accounted for

You already paid IRAS the $900 GST
Can't claim relief if you never declared the output tax

4. No actual payment received

Debtor hasn't paid (even partially)
If partial payment, can only claim relief on unpaid portion

How to claim:

Step 1: Write off the debt Document in your accounting records that debt is written off.

Step 2: Complete self-review checklist IRAS provides Self-review of Eligibility to Claim Bad Debt Relief checklist.

Complete it. Keep it in your files (don't submit to IRAS, but must maintain as records).

Step 3: Claim in GST return

Include relief amount in Box 7 (Input tax and refunds claimed)
Indicate "Yes" in Box 11 (bad debt relief claims)
State the amount claimed

Example:

Q1 2024: Invoiced customer $10,000 + $900 GST

Declared in Box 1: $10,000
Declared in Box 6: $900

Q3 2024: Customer still hasn't paid (6 months passed)

Written off debt
Completed eligibility checklist
Claim relief in Q3 return:
- Box 7: Include $900
- Box 11: "Yes", amount $900

If customer later pays:

Customer miraculously pays in Q1 2025.

Requirement: Must repay the bad debt relief to IRAS

Box 6: Include $900 (repay output tax)
This reverses the relief claimed

Partial recovery:

Customer pays $5,000 (half the debt).

Already claimed relief on full $900
Must repay proportionate amount: $5,000/$10,000 × $900 = $450
Box 6: Include $450

Common mistakes:

Mistake 1: Claiming too early

Debt only 4 months old: Not eligible yet (need 6 months)
Wait until time requirement met

Mistake 2: No documentation

Didn't write off in accounts: Not eligible
Didn't complete self-review checklist: Can't support claim on audit

Mistake 3: Claiming on debt where original output tax not declared

Forgot to declare sale in original return
Can't claim relief if you never paid output tax in first place

Credit Notes: Adjusting Previous Declarations

Issued credit note to customer? Deduct from current return.

When credit notes arise:

Customer returns goods
Price adjustment after delivery
Error in original invoice (overcharged)
Settlement discount taken

How to handle in GST filing:

Scenario 1: Credit note in same quarter as original invoice

Q1: Invoice $10,000 + $900 GST
Q1: Credit note $1,000 + $90 GST (same quarter)

Q1 filing:

Box 1: $9,000 (net after credit note)
Box 6: $810 (net GST)

Simple. Just declare the net amount.

Scenario 2: Credit note in different quarter

Q1: Invoice $10,000 + $900 GST
- Q1 filing: Box 1 = $10,000, Box 6 = $900
Q2: Credit note $1,000 + $90 GST

Q2 filing:

Box 1: Deduct $1,000 (from your Q2 sales)
Box 6: Deduct $90 (from your Q2 output tax)

The credit note reduces your current quarter's figures.

What this means:

If your Q2 sales were $50,000 before the credit note:

Box 1: $49,000 ($50,000 - $1,000)
Box 6: $4,320 ($4,500 - $90)

Scenario 3: Multiple credit notes

Q1: Original invoice $100,000
Q2: Credit note $10,000
Q3: Credit note $5,000

Q2 filing: Deduct $10,000 Q3 filing: Deduct $5,000

Each credit note reduces the quarter in which it's issued.

Credit notes RECEIVED (from suppliers):

If supplier issues you credit note:

Deduct from Box 5 (taxable purchases)
Deduct from Box 7 (input tax)

Same principle, just on the purchase side.

Import GST: Claiming on Goods Brought In

Paid GST when importing goods? Claim it in Box 7.

How import GST works:

At import (Singapore Customs):

You pay GST based on import permit
Import permit shows GST amount
This GST is claimable (if for business use)

In your GST return:

Box 5: Include value of imported goods (excluding GST)
Box 7: Include import GST paid

Example:

Imported machinery:

CIF value: $100,000
Import GST paid: $9,000
Import permit shows these amounts

GST filing:

Box 5: $100,000
Box 7: $9,000

Key requirement: Must have import permit showing GST paid.

Without import permit, can't prove you paid GST, can't claim.

Special schemes:

Major Exporter Scheme (MES):

GST suspended on imports
Don't pay import GST
Can't claim input tax (because didn't pay any)
Declare import value in Box 9

Import GST Deferment Scheme (IGDS):

GST deferred (not suspended)
Account for it in your GST return
Special boxes (18-21) for IGDS reporting

Licensed warehouse / Zero-GST warehouse:

GST suspended while goods in warehouse
Pay GST when removing goods from warehouse
Claim based on removal permit

Adjustments to Previous Returns: Small Errors

Discovered error in previous quarter's return? You can adjust in current return IF error is small.

IRAS threshold for self-correction:

Can adjust in current return if:

Net GST error ≤ $3,000, AND
Other box errors ≤ 5% of Box 4 (total supplies) from the affected return

What counts as "net GST error":

Difference between:

Additional output tax (Box 6) you should have declared
Additional input tax (Box 7) you should have claimed

Example 1: Small error (can self-correct)

Q1 return (originally filed):

Box 1: $90,000
Box 6: $8,100

Discovered error: Forgot to include one invoice $5,000 + $450 GST

Error assessment:

Additional output tax: $450
Net GST error: $450 (under $3,000 threshold)
Box 1 error: $5,000 / $90,000 = 5.5% (slightly over 5%, but close)

Correction in Q2 return: Add $5,000 to Q2 Box 1 and $450 to Q2 Box 6

Include note in "Additional Information" section explaining adjustment.

Example 2: Large error (must file amendment)

Q1 return (originally filed):

Box 1: $50,000
Box 6: $4,500

Discovered error: Forgot entire project $40,000 + $3,600 GST

Error assessment:

Net GST error: $3,600 (exceeds $3,000 threshold)
Cannot self-correct

Requirement: File GST F7 (Disclosure of Errors) for Q1

Don't try to adjust in current return. Must amend the original return.

Box 16: Adjustments field

When making adjustments to previous returns, document in Box 16 (if your form has this field) or in Additional Information section.

Explain:

Which quarter being adjusted
Nature of error
Amount of adjustment

Pre-Registration Input Tax Claims

Claimed GST on expenses before you registered? Can claim it in your first GST return.

Eligibility:

1. Time limit

Expenses incurred up to 6 months before registration date
Example: Registered 1 July, can claim expenses back to 1 January

2. Must relate to taxable supplies

Expense must be for taxable supplies you'll make after registration
Can't claim if for exempt supplies

3. Proper tax invoices

Must have tax invoices in your company name
Invoices issued before registration

4. Goods/services not yet consumed

For goods: Must still hold them (not fully consumed/sold before registration)
For services: Can claim regardless

Common claimable items:

Before registration, you incurred:

Incorporation costs (legal, accounting): Claimable
Office setup (furniture, computers): Claimable if still holding them
Website development: Claimable
Marketing materials: Claimable if not yet distributed
Rent deposit: Claimable

How to claim:

First GST return only:

Box 5: Include value of pre-registration purchases
Box 7: Include GST from those purchases
Box 12: Select "Yes" and state amount

Self-review checklist:

IRAS provides Pre-registration GST Checklist.

Complete it, keep it in records (don't submit).

Example:

Registered for GST: 1 April 2025

Pre-registration expenses (Jan-Mar 2025):

Office furniture: $5,000 + $450 GST (purchased Feb, still using)
Marketing consultant: $3,000 + $270 GST (hired Mar)
Rental deposit: $10,000 + $900 GST (paid Jan)

First GST return (Q2 2025):

Box 5: Include $18,000
Box 7: Include $1,620
Box 12: "Yes", $1,620

What you CAN'T claim:

Expenses more than 6 months before registration
Expenses for private use
Goods fully consumed before registration (e.g., office supplies used up)
Expenses without proper tax invoices

Voluntary Disclosure of Errors

Made significant errors across multiple returns? Voluntary disclosure is better than waiting for IRAS to find them.

When to consider voluntary disclosure:

Multiple quarters with errors
Large dollar amount errors
Systematic error (same mistake repeated)
Discovered errors during internal review

Benefits of voluntary disclosure:

1. Reduced penalties IRAS treats voluntary disclosure more leniently than discovered errors.

2. Avoid prosecution Serious errors could lead to prosecution. Voluntary disclosure shows good faith.

How to submit:

Option 1: Amend via myTax Portal

File GST F7 (Disclosure of Errors) for each affected quarter
Pay the additional GST owed

Option 2: Write to IRAS For complex situations, write formal letter:

Explain what errors occurred
Why they occurred
How you discovered them
Steps taken to prevent recurrence
Proposed payment plan (if needed)

What to expect:

IRAS will:

Review your disclosure
Calculate total GST owed plus penalties
May reduce penalties (discretionary)
Approve or modify payment plan

Example scenario:

Discovered you've been incorrectly claiming input tax on motor cars for 2 years (8 quarters).

Total error: $36,000 input tax wrongly claimed

Steps:

Calculate exact error across all quarters
Prepare voluntary disclosure letter
File amended returns (F7) for all affected quarters
Request payment plan ($36,000 over 12 months)
Submit to IRAS

Voluntary disclosure doesn't eliminate penalties, but significantly reduces them compared to IRAS discovering the error through audit.

When to Seek Professional Help

These special cases require careful handling:

Get professional advice if:

Multiple bad debts (ensure proper documentation)
Large credit note adjustments spanning several quarters
Complex import arrangements (MES, IGDS, warehousing)
Discovered systematic errors requiring voluntary disclosure
Pre-registration claims exceeding $10,000
Partially exempt business making adjustments

Errors in special cases often trigger IRAS queries or audits. Professional guidance prevents costly mistakes.

Our monthly bookkeeping service includes proper handling of all these adjustments and special cases, with documentation that withstands IRAS scrutiny.

Additional Complexities and Edge Cases

Some situations don't fit standard filing but come up often enough to address.

Foreign Currency Transactions

All GST returns must be in Singapore dollars. If you transact in foreign currency, conversion is required.

Which exchange rate to use:

For sales (output tax): Use exchange rate on the earlier of:

Invoice date
Payment received date

For purchases (input tax): Use exchange rate on the earlier of:

Invoice date
Payment made date

Be consistent: Once you choose a rate for a transaction, stick with it across all GST boxes.

Example: Export Invoice in USD

Invoice issued: 15 March, USD $10,000

SGD/USD rate on 15 March: 1.35
SGD equivalent: $13,500

GST filing:

Box 2 (zero-rated): $13,500
Use this $13,500 regardless of actual payment received later

Customer pays: 30 April

SGD/USD rate on 30 April: 1.38
Actual SGD received: $13,800

Foreign exchange gain: $300

This is not a GST issue
Record as FX gain in accounting, not in GST return
Box 2 still shows $13,500

Example: Purchase Invoice in EUR

Supplier invoice: 20 February, EUR €8,000 + €720 GST

SGD/EUR rate on 20 February: 1.45
SGD equivalent: €8,000 × 1.45 = $11,600
GST: €720 × 1.45 = $1,044

GST filing:

Box 5: $11,600
Box 7: $1,044

Payment made: 25 March at different rate

Foreign exchange difference is not a GST issue
Use original invoice date rate for GST purposes

Practical tip:

Most accounting software handles currency conversion automatically using invoice date rates. Verify it's using the correct rate before filing.

Export Documentation Requirements

Claiming zero-rating for exports? You need proper documentation.

Required documents:

For goods physically exported:

Export permit from Singapore Customs
Commercial invoice showing customer details
Bill of lading or airway bill (proof of export)
Proof of payment received

Without export permit: Can't claim zero-rating. Must charge GST.

Example mistake:

Sold goods to overseas customer, shipped from Singapore:

You have invoice and payment proof
But forgot to obtain export permit

Result: Can't claim zero-rating in Box 2. Must declare as standard-rated in Box 1 and charge 9% GST.

If you already invoiced without GST (expecting zero-rating), you're now short $900 you need to pay IRAS out of pocket.

Always obtain export permit before claiming zero-rating.

For international services:

Documentation depends on service type:

Customer location (must be overseas)
Service qualifies under Section 21(3) of GST Act
Contract showing service provided to overseas party
Correspondence proving customer location

Less prescriptive than goods export, but must demonstrate customer is overseas business and service qualifies as international.

Common documentation issues:

Issue 1: Customer's address unclear

Invoice shows overseas customer but service delivered in Singapore.

Example: Training provided to overseas company but conducted in Singapore.

Not zero-rated (service performed in Singapore)
Must charge GST

Issue 2: Middleman situation

Sold to Singapore company who then exports:

Your sale to Singapore company: Standard-rated (charge GST)
Their export: They claim zero-rating

You can't claim zero-rating just because your customer intends to export. You're selling to Singapore party.

Issue 3: Missing export permit

Goods left Singapore but no proper export permit obtained:

Singapore Customs may not have record
IRAS will disallow zero-rating on audit
You owe back GST plus penalties

Amended Returns Process

Need to correct a filed return? Use Form GST F7.

When to file F7:

Must file F7 if error exceeds self-correction thresholds:

Net GST error > $3,000, OR
Other box errors > 5% of original Box 4

How to file:

Step 1: Log into myTax Portal

Navigate to GST section
Select "Amend GST Return" or "File F7"

Step 2: Select affected quarter Choose which quarter's return you're correcting.

Step 3: Complete F7 form

Show original figures
Show corrected figures
Explain the error in Additional Information section

Step 4: Pay additional GST (if owe more) If amendment results in additional GST owed, must pay immediately.

Step 5: Submit IRAS processes amendments and may send queries.

Penalties for amended returns:

If you caught the error (voluntary amendment):

Reduced penalties (IRAS discretion)
Shows good faith

If IRAS caught the error (forced amendment):

Full penalties apply
Potential prosecution if serious or repeated

Time limits:

No strict time limit, but:

IRAS can assess back 4 years
Earlier you amend, better
Don't wait for audit to fix known errors

Multiple quarter errors:

File separate F7 for each affected quarter.

If errors span many quarters, consider comprehensive voluntary disclosure letter to IRAS explaining systematic issue and how you're fixing it.

Mixed Supply Complexities

Single transaction with elements subject to different GST treatments.

Example: Bundled Package

Hotel package: $1,000

Room (standard-rated): $700
Airport transfer (standard-rated): $200
Minibar (standard-rated): $100

Simple: Everything standard-rated, charge 9% on $1,000.

Example: Complex Bundle

Property developer sells commercial unit with residential car park:

Commercial space (standard-rated): $1.5M
Residential car park (exempt): $100K

Cannot treat as single supply.

Must split:

Box 1: $1.5M (charge GST on this)
Box 3: $100K (exempt, no GST)

Apportionment required: If not separately stated in contract, must reasonably apportion based on market values.

IRAS may challenge apportionment if appears contrived to minimize GST.

Principal vs ancillary supplies:

Sometimes one element is principal, others are ancillary.

Example: Sell equipment with installation:

Equipment (principal supply)
Installation (ancillary to equipment sale)

Treat as single supply at equipment's GST rate.

But if installation is substantial (e.g., installation fee equals equipment cost), IRAS may argue they're separate supplies.

Grey areas require judgment. Document your reasoning.

Reverse Charge Edge Cases

Beyond basic reverse charge, some scenarios get complicated.

Scenario: Imported service partly for taxable, partly for exempt supplies

Overseas consultant fee: $10,000

Your business:

80% taxable supplies
20% exempt supplies

Reverse charge treatment:

Box 1: $10,000 (full amount)
Box 6: $900 (output tax on full amount)
Box 5: $10,000
Box 7: $720 (input tax claim = $900 × 80%)

You owe IRAS net $180.

Scenario: Re-charge imported service to customer

You engage overseas consultant: $10,000 You re-invoice customer: $10,000 + your markup

Your filing:

Reverse charge on imported service (as above)
Plus declare your re-charge to customer as standard-rated supply

Both transactions appear in same return.

Scenario: Imported service not used (project cancelled)

Engaged overseas consultant but project cancelled before service used.

Reverse charge still applies:

Must account for output tax (Box 6)
But can you claim input tax (Box 7)?

Depends: If service genuinely not used for any business purpose, IRAS may disallow input tax claim.

Complex area. Get advice if significant amounts involved.

Electronic Marketplace and Platform Supplies

Operating digital platforms? Special GST rules apply (Boxes 14-17).

These rules are complex and beyond scope of this article.

If you're:

Electronic marketplace operator
Redeliverer of imported low-value goods
Platform supplying services on behalf of third parties

You need specialist advice. The filing requirements are extensive and penalties for errors are severe.

Most SMEs: These boxes don't apply. Select "No" and move on.

When It Gets Too Complex

If you're dealing with:

Multiple foreign currencies
Regular exports requiring documentation
Reverse charge on substantial imported services
Mixed supplies with complex apportionment
Platform/marketplace operations

You likely need professional help. The compliance burden and error risk are too high for DIY.

For comprehensive coverage of common GST mistakes, see: Common GST Mistakes Singapore Businesses Make.

Our monthly bookkeeping service handles these complexities as part of standard service. We deal with foreign currency, export documentation, and reverse charge situations regularly.

After Filing: What Happens Next

You've submitted your GST return. Now what?

Payment Process (If You Owe GST)

Box 8 is positive: You owe IRAS money.

Payment deadline: Same as filing deadline

Q1: 30 April
Q2: 31 July
Q3: 31 October
Q4: 31 January

Payment methods:

GIRO (recommended):

If set up, IRAS auto-deducts from your bank account
Usually 10-14 days after filing
No action needed from you
Verify deduction occurred

Internet banking:

Log into business bank account
Select "Pay Government Agencies" or "IRAS Payment"
Enter GST payment details
Use your GST registration number as reference
Immediate payment

Via myTax Portal:

Log into myTax Portal
Go to "Payments" section
Select "Pay GST"
Choose payment method (credit card or online banking)
Follow prompts

Cheque (not recommended):

Write cheque to "Commissioner of Goods and Services Tax"
Mail to IRAS (address on myTax Portal)
Slow processing
No immediate confirmation

Payment confirmation:

Save proof of payment:

Bank transaction record
GIRO deduction confirmation
Payment receipt from myTax Portal

Keep in your GST records (may need to prove payment on audit).

Late payment consequences:

5% penalty if GST remains unpaid more than 60 days after deadline:

Example: Owe $10,000, unpaid for 61 days → Additional $500 penalty

Interest charges on unpaid amount:

Compounds monthly
Current rate available on IRAS website

Collection action:

IRAS may take legal action
Court judgment against company
Directors may become personally liable in certain cases

Pay on time. Even if cash flow tight, pay the GST. It's not your money (you collected it from customers).

Refund Process (If IRAS Owes You)

Box 8 is negative: IRAS owes you refund.

Processing time:

Standard refunds: 4-6 weeks

Routine processing
Minimal review

Large refunds: 6-12 weeks or longer

IRAS reviews more carefully
May send queries before releasing refund

What IRAS reviews:

Before releasing refund, IRAS checks:

Input tax claims reasonable for your business type
Export documentation (if claiming zero-rating)
No unusual patterns
Compliance history

Queries before refund:

IRAS may request:

Supporting invoices for input tax claims
Export permits for zero-rated supplies
Explanation of why refund is so large
Additional business information

Respond promptly. Refund frozen until you answer satisfactorily.

Refund payment:

Refund goes directly to bank account registered with IRAS.

Verify:

Correct bank account on file with IRAS
Update if changed banks

If refund doesn't arrive:

After 8 weeks, check myTax Portal:

Look for status updates
Check for queries you may have missed

Contact IRAS if no update and no refund received.

Persistent refunds:

Getting refund every quarter?

IRAS may investigate:

Is your business genuinely in refund position?
Export-heavy businesses: Normal
High capital expenditure: Temporary refund position acceptable
No clear reason: IRAS gets suspicious

Be prepared to explain why your input tax consistently exceeds output tax.

IRAS Queries and Correspondence

IRAS may send queries even if no refund claimed.

Common reasons for queries:

1. Unusual figures

Sudden spike in sales or purchases
Very different from previous quarters
Doesn't match industry norms

2. Zero-rating claims

Large zero-rated supplies (exports)
IRAS wants to verify export documentation

3. Input tax claims

High proportion of input tax to output tax
Claims in disallowed categories (cars, entertainment)

4. Late filing

Even if filed late, IRAS may query why
Repeated late filing triggers closer scrutiny

5. Random review

IRAS randomly selects returns for spot checks
Not necessarily because something's wrong

How IRAS contacts you:

myTax Mail:

Check myTax Portal regularly
Queries sent electronically

Physical letter:

To registered business address
Update ACRA if address changed

Email:

If you've provided email to IRAS
Verify sender is legitimate IRAS email

Phone:

Sometimes IRAS calls for clarification
Verify caller identity (ask for reference number, call back IRAS main line)

Responding to queries:

Read carefully:

What exactly is IRAS asking?
What documents do they need?
What's the deadline?

Gather documents:

Tax invoices
Export permits
Contracts
Payment records
Whatever IRAS requested

Respond by deadline:

Usually 14-21 days given
Request extension if need more time
Don't ignore (penalties and legal action possible)

Be clear and complete:

Answer all questions asked
Provide all requested documents
Explain clearly if situation is complex

Don't ignore queries.

Ignoring IRAS correspondence:

Escalates to formal investigation
May result in audit
Penalties for non-cooperation
Potential prosecution

GST Audits

IRAS may conduct comprehensive audit of your GST returns.

What triggers audits:

1. Risk indicators

Persistent late filing
Large or frequent refunds
Industry known for non-compliance
Queries revealed issues

2. Random selection

IRAS randomly audits businesses
Part of compliance programme

3. Tip-offs

Competitor complaints
Disgruntled employee reports
Cross-checks with other data

4. Related party audits

Your supplier/customer being audited
IRAS cross-checks your records

What audit involves:

Notice of audit:

IRAS sends letter stating intention to audit
Lists periods to be audited (usually 2-4 years)
Requests documents and information

Document requests:

All GST returns for audit period
Sales invoices and records
Purchase invoices and records
Bank statements
Accounting records
Contracts with major customers/suppliers
Export/import documentation

Audit visit:

IRAS officers visit your office
Interview directors and accounting staff
Inspect records and systems
May be 1 day or several days depending on complexity

Findings:

No issues found:

Audit closes
Letter confirming compliance

Errors found:

IRAS issues assessment for additional GST owed
Plus penalties (typically 5-50% of underpaid GST)
Plus interest
Must pay within deadline

Serious issues:

Potential prosecution for tax evasion
Directors may be personally liable
Company reputation damaged

How to handle audit:

Cooperate fully:

Provide all requested documents
Answer questions honestly

Get professional help:

Engage accountant or tax advisor
Let them liaise with IRAS
Professional representation reduces stress and errors

Review findings:

If you disagree with IRAS assessment, you can object
Must object within 30 days
Provide reasons and evidence

Preventing audits:

Can't completely avoid (random audits happen), but reduce risk:

File on time, every time
Keep proper records
Don't claim what's clearly disallowed
Respond promptly to any queries
Maintain consistent compliance

Record Keeping Requirements

IRAS requires you to keep all GST records for 5 years.

Records to maintain:

Sales records:

All tax invoices issued
Credit notes issued
Receipts for payments received
Contracts with customers
Delivery notes
Export permits and documentation

Purchase records:

All tax invoices received from suppliers
Credit notes received
Receipts for payments made
Import permits
Contracts with suppliers

Accounting records:

General ledger
Sales ledger
Purchase ledger
Bank statements
Cash books
GST working papers (calculations used for filing)

GST returns:

Copies of all filed returns
Confirmations of filing
Payment receipts

Format:

Electronic records acceptable:

Scanned invoices
Digital invoices (PDF)
Accounting software records

Must be retrievable:

Can produce on demand if IRAS requests
Organized (not just dumped in folders)

Backup:

Keep backups of electronic records
Cloud storage or external drives
Protect against data loss

Physical storage:

Secure location
Protected from damage (fire, flood, etc.)

Retention period:

5 years from end of accounting period:

Example:

Q1 2025 return (Jan-Mar 2025)
Keep records until 31 March 2030

If audit ongoing: Keep records until audit completed, even if beyond 5 years.

Penalties for poor record keeping:

Can't produce records when IRAS requests:

Penalties up to $5,000
IRAS may estimate your GST liability (usually high)
Prosecution possible for serious cases

Keep your records. Storage is cheap compared to penalties.

Compliance Tips

Best practices for ongoing compliance:

1. Monthly bookkeeping

Update records every month
Don't wait until quarter-end
Makes filing easier and more accurate

2. Set reminders

2 months before deadline: Start preparing
2 weeks before deadline: Final review
3 days before deadline: File

3. Review before filing

Check all figures
Verify calculations
Ensure all invoices included

4. Document everything

Why you claimed zero-rating
Why expense is business use
Anything IRAS might question

5. Seek clarification

If unsure about treatment, ask IRAS
Or consult accountant
Don't guess and hope for best

6. Monitor myTax Portal

Check weekly for correspondence
Respond promptly to any queries

7. Update IRAS of changes

Change of address
Change of bank account
Change of business activities

The goal: Boring, predictable compliance. No surprises, no queries, no audits.

Our monthly bookkeeping service includes all record keeping and compliance management. We maintain your records in audit-ready format and respond to any IRAS queries on your behalf.

DIY vs Professional Help: The Real Cost

You now understand the GST filing process. But should you do it yourself?

Let's do the actual math.

Time Cost of DIY Filing

If your records are organized monthly:

Time per quarter:

Review all transactions: 30-45 minutes
Calculate Box 1-7 figures: 30-45 minutes
Log into myTax Portal and file: 15-30 minutes
Make payment and save records: 15 minutes

Total: 1.5-2 hours per quarter

Annual time: 6-8 hours

At $100/hour opportunity cost = $600-800/year

If your records are messy:

Time per quarter:

Sort through receipts and invoices: 2-3 hours
Reconcile bank statements: 1-2 hours
Figure out what's claimable: 1-2 hours
Calculate all boxes: 1 hour
File: 30 minutes
Fix errors after IRAS queries: 2-4 hours (if mistakes made)

Total: 5-10 hours per quarter

Annual time: 20-40 hours

At $100/hour opportunity cost = $2,000-4,000/year

Reality check:

Most business owners bill clients $100-500/hour. Spending 20-40 hours on GST filing = losing $2,000-20,000 in potential revenue.

Risk Cost of DIY Errors

Even organized business owners make mistakes.

Common DIY errors and costs:

Error 1: Including GST in Box 1

Overstated sales by 9%
Overpaid GST by 9% of 9% = 0.81%
On $500K sales: Overpaid $4,050/year

Error 2: Claiming disallowed input tax

Claimed GST on car expenses: $5,000
IRAS audit disallows: Must repay $5,000 + penalty $500-2,500
Total cost: $5,500-7,500

Error 3: Wrong timing of supplies

Declared deposit in wrong quarter
Late filing penalty: $200-1,000
Plus stress dealing with IRAS correspondence

Error 4: Missing export documentation

Claimed zero-rating without proper permits
IRAS disallows: Must pay GST on $100K sales = $9,000
Plus penalty 10-50% = $900-4,500
Total: $9,900-13,500

Error 5: Incorrect apportionment (partially exempt business)

Claimed 100% input tax instead of 70%
Overclaimed $10,000 over 2 years
Repay $10,000 + penalties $1,000-5,000
Total: $11,000-15,000

One significant error wipes out years of "savings" from DIY.

Professional GST Filing Costs

Option 1: GST filing only (quarterly service)

Cost: $250-400 per quarter

Annual: $1,000-1,600/year

What's included:

Review your transaction records
Calculate all GST boxes
File GST return
Handle IRAS queries (if any)

What's NOT included:

Monthly bookkeeping (you still do this)
Tax planning or optimization
Financial statements
Other compliance (ACRA, tax filing)

Best for:

Very organized businesses
Simple transaction structures
Already doing monthly bookkeeping yourself
Just need filing expertise

Option 2: Monthly bookkeeping (includes GST filing)

Cost: $7,000-15,000/year

What's included:

Monthly bookkeeping (all transactions recorded)
Bank reconciliation
Financial reports monthly
Quarterly GST filing (included)
Annual corporate tax filing (included)
IR8A filing (included)
ACRA filing (included)
IRAS query handling
Tax planning advice

Best for:

Most SMEs
Don't have time for bookkeeping
Want comprehensive compliance
Value peace of mind

Transaction-based pricing:

Low volume (<50 transactions/month): $7,000-8,000/year
Medium volume (50-150 transactions/month): $10,000-12,000/year
High volume (150+ transactions/month): $13,000-15,000/year

The Real Comparison

Let's compare all costs, not just service fees.

Scenario: SME with $800,000 revenue, 80 transactions/month

Option A: Complete DIY

Your time: 30 hours/year × $150/hour = $4,500
Risk of errors: 30% chance × $3,000 average cost = $900
Stress and anxiety: Unquantifiable
Total expected cost: $5,400/year

Option B: DIY bookkeeping + quarterly GST filing service

Your bookkeeping time: 60 hours/year × $150/hour = $9,000
GST filing service: $1,200/year
Reduced error risk: 10% × $1,500 = $150
Total expected cost: $10,350/year

Option C: Full monthly bookkeeping service

Service cost: $11,000/year
Your time: 0 hours
Error risk: Near zero (accountant has insurance)
Total cost: $11,000/year

Option D: Cheap accountant ($3,000/year)

Service cost: $3,000/year
Your time chasing them: 10 hours × $150 = $1,500
Error risk (disorganized service): 20% × $2,000 = $400
Missed tax optimization: $1,500/year
Total cost: $6,400/year

But wait, factor in tax optimization:

Professional accountant typically saves:

Proper expense claims: $1,000-2,000/year
Timing of revenue/expenses: $1,000-3,000/year
Eligible reliefs and schemes: $500-2,000/year
Total tax savings: $2,500-7,000/year

Revised comparison:

Option A (DIY):

Cost: $5,400
No tax optimization: $0
Net cost: $5,400

Option C (Professional service):

Cost: $11,000
Tax savings: $4,000 (conservative)
Net cost: $7,000

Difference: $1,600 more for professional service

But you get:

Zero time spent on bookkeeping
Zero stress about GST filing
Zero risk of penalties
Monthly financial reports
Someone to call with questions
Complete compliance (not just GST)

Most business owners: Professional service is worth the extra $1,600/year.

When DIY Makes Sense

Consider DIY if:

1. Very simple business

<20 transactions per month
Only standard-rated supplies (no exports, no exemptions)
No employees (no IR8A complexity)
You actually enjoy bookkeeping

2. You have time

Not sacrificing client work or business development
Genuinely have 2-3 hours per quarter spare

3. You're comfortable with complexity

Understand GST rules thoroughly
Confident interpreting IRAS guidance
Can handle queries yourself

4. You're organized

Monthly bookkeeping already done
Records always up to date
Clear systems in place

Realistic assessment: <5% of SMEs meet all these criteria.

When to Hire Professional Help

Hire immediately if:

1. Already missed deadlines

Facing penalties
Need catch-up work
Want to prevent future late filing

2. Complex business structure

Exports or imports
Partially exempt supplies
Reverse charge on imported services
Related party transactions

3. High transaction volume

100 transactions per month
Can't keep up with record-keeping

4. Been audited before

IRAS found issues
Need clean compliance going forward

5. Your time is valuable

Bill clients >$200/hour
20 hours on bookkeeping = $4,000 lost revenue
Professional service costs less

6. You've made errors before

Received IRAS queries
Paid penalties
Don't want to repeat mistakes

7. Growing rapidly

Can't scale DIY bookkeeping
Need proper financial visibility
Preparing for financing/investors

8. Just don't want to deal with it

Valid reason
Focus on what you do best
Delegate compliance to experts

Honest truth: Most business owners should outsource GST filing and bookkeeping.

What About Accounting Software?

"Can't I just use Xero/QuickBooks and file myself?"

Software helps but doesn't solve everything:

What software does well:

Records transactions
Tracks GST on each transaction
Calculates Box 1, 5, 6, 7 automatically (if coded correctly)
Generates GST reports

What software doesn't do:

Know if your GST coding is correct
Identify disallowed input tax claims
Handle complex scenarios (reverse charge, apportionment)
Respond to IRAS queries
Keep you compliant with changing rules
Optimize your tax position

Software + DIY:

Cost: $50-70/month = $600-840/year
Your time: Still 10-15 hours/year
Error risk: Reduced but not eliminated
Total cost: $2,100-3,000/year

Still more expensive than you think once you factor in time and errors.

Software + Accountant: Best combination. Accountant uses software (efficiency) but provides expertise.

Our monthly bookkeeping service includes Xero/QuickBooks setup and maintenance. You get the software benefits plus expert oversight.

The Bottom Line

For 95% of Singapore SMEs, professional help is cheaper than DIY once you factor in:

Your time opportunity cost
Error risk and penalties
Tax optimization missed
Stress and mental burden

The $7,000-15,000/year for professional service pays for itself through:

Penalties avoided: $1,000-5,000/year
Tax savings from optimization: $2,000-5,000/year
Your time freed up: 50-80 hours/year

Net benefit: $3,000-10,000/year positive return on investment

Frequently Asked Questions

What if I make a mistake after filing my GST return?

Depends on the size of the error. If the net GST error is $3,000 or less AND other box errors are within 5% of your original Box 4, you can correct it in your next GST return. Just add or deduct the correction amount in the current quarter's filing and note the adjustment in Additional Information.

If the error exceeds these thresholds, you must file Form GST F7 (amendment) for the affected quarter via myTax Portal.

Caught the error yourself? IRAS treats voluntary corrections more leniently. Waiting for them to find it? Expect full penalties.

Can I file GST monthly instead of quarterly?

Yes, but only if IRAS approves your application. Monthly filing is typically for large businesses or those with consistent refund positions (like exporters).

Most SMEs file quarterly. Unless you have a specific business reason, stick with quarterly - less administrative burden.

What happens if my input tax is always higher than output tax?

You'll get refunds every quarter. This is normal for:

Export-heavy businesses (zero-rated sales, but pay GST on local purchases)
Businesses with high capital expenditure periods
New businesses building up inventory

IRAS may query persistent refunds to verify they're genuine. Be prepared to explain your business model and provide supporting documents.

Consistent refunds aren't a problem if they're legitimate. But if there's no clear reason, IRAS gets suspicious.

Do I need to file if I have no business activity that quarter?

Yes. You must file a nil return (enter $0 in all boxes).

Not filing because you had no activity still counts as late filing. Penalty: $200 minimum.

File the nil return. Takes 5 minutes.

Can I claim GST on purchases made before I registered?

Yes, up to 6 months before your registration date, but only in your first GST return.

Conditions:

Must have proper tax invoices in your company name
Expenses must relate to taxable supplies you'll make after registration
For goods: Must still hold them (not fully consumed before registration)
Complete IRAS self-review checklist

Claim in Box 7 and indicate "Yes" in Box 12 (pre-registration claims).

What if Singapore Customs didn't issue me an export permit?

Then you can't claim zero-rating. Must charge GST as standard-rated supply.

If you already invoiced without GST (expecting zero-rating), you now owe IRAS the 9% GST out of pocket.

Always obtain export permit before claiming zero-rating. No permit = no zero-rating, regardless of whether goods actually left Singapore.

How long does it take to get a GST refund?

Standard refunds: 4-6 weeks

Large refunds: 6-12 weeks or longer (IRAS reviews more carefully)

IRAS may send queries before releasing refund. Respond promptly or refund stays frozen.

If no refund after 8 weeks, check myTax Portal for updates or contact IRAS.

Can I claim GST on meals and entertainment?

Generally no, unless you meet specific conditions.

Entertainment expenses (meals, drinks, events) are disallowed EXCEPT when:

Provided to customers (not your own staff)
In course of business (client meetings, negotiations)
Properly documented (who attended, business purpose)
Reasonable in relation to business

Staff meals, team dinners, and directors' meals without customers present: Not claimable.

Documentation is critical. Without records of attendees and business purpose, IRAS will disallow on audit.

What if I can't pay my supplier within 12 months?

You must repay the input tax you claimed to IRAS.

Example: Claimed $900 input tax in Q1 2024. Still unpaid to supplier 12 months later (Q1 2025). You must repay $900 to IRAS in Q1 2025 filing.

If you later pay the supplier, you can claim the input tax again in that quarter.

This prevents businesses from claiming input tax on invoices they never intend to pay.

Can I claim GST on my company car?

Generally no. Motor cars are disallowed under GST regulations.

Exceptions where you CAN claim:

Licensed taxi
Driving school vehicle
Car dealer (cars held as stock)
Car rental company

Goods vehicles (vans, lorries) designed for carrying goods: Input tax claimable if for business use.

Motorcycles: Not classified as motor cars, so input tax claimable for business use.

The vehicle's registration category matters - commercial vehicle vs private car.

What happens if IRAS audits me?

IRAS sends notice stating:

Periods to be audited (usually 2-4 years)
Documents required
Audit date (if office visit planned)

You must:

Provide all requested documents
Answer questions honestly
Allow IRAS officers access to records

After audit:

No issues: Audit closes, letter confirming compliance
Errors found: Assessment for additional GST + penalties (5-50%) + interest
Serious issues: Potential prosecution

Get professional help immediately upon receiving audit notice. Accountant or tax advisor can represent you and minimize penalties.

Can I change my financial year-end after GST registration?

Yes, but all your GST deadlines shift to match the new FYE.

Notify IRAS in writing before making the change.

During transition, you may have a short financial period (e.g., 6 months). Must file GST for this short period.

Affects ECI and corporate tax filing deadlines, not just GST. Inform your accountant immediately if changing FYE.

What if I registered my business under the wrong GST scheme?

Contact IRAS immediately to correct.

For example:

Registered as standard GST when you should be under Import GST Deferment Scheme
Or vice versa

IRAS can help transfer you to the correct scheme, but the sooner you fix it, the less complicated.

Don't wait until you've filed multiple returns incorrectly.

How do I cancel my GST registration?

If annual taxable turnover falls below $1 million for 12 months, you can apply to cancel.

Process:

Apply via myTax Portal (at least 30 days before intended cancellation date)
IRAS reviews and approves
File final GST return (Form F8)
Account for GST on assets still held
Pay any outstanding GST

Can't cancel immediately - there's a formal process and final accounting requirements.

Also consider: Voluntary registration has minimum 2-year commitment before you can cancel.

What's the difference between standard-rated and zero-rated?

Both are taxable supplies, but:

Standard-rated: 9% GST charged

Most domestic sales in Singapore
Declare in Box 1, charge customer 9%

Zero-rated: 0% GST charged

International services and exports
Declare in Box 2, charge customer 0%

Why distinction matters:

For zero-rated supplies, you can still claim input tax on related expenses.

For exempt supplies, you cannot claim input tax.

Zero-rated is better than exempt from a GST perspective.

Can I offset a refund from one quarter against GST owed in the next quarter?

No. Each quarter is filed and settled separately.

Q1 refund: IRAS pays you Q2 owe: You pay IRAS

No automatic offsetting across quarters.

Exception: If refund amount is less than $5, it's not paid out and not carried forward either. Just forfeited.

What if I lose all my invoices in a fire/flood/disaster?

You still need to file GST return. Reconstruct records as best as possible:

Bank statements (show payments in/out)
Contracts and agreements
Email correspondence
Customer/supplier records
Alternative documentation

File based on reconstructed records. Explain situation to IRAS in Additional Information.

For input tax claims without invoices: IRAS may disallow without proper tax invoices, but they'll consider extenuating circumstances.

Prevention: Keep digital backups of all invoices. Cloud storage survives physical disasters.

Do I need to charge GST to overseas customers?

Depends on what you're supplying:

Goods exported: Zero-rated (0% GST) - if you have export documentation

Services to overseas business customer: Generally zero-rated (0% GST) - if service qualifies as international service under Section 21(3)

Services to overseas individual: May be standard-rated (9% GST) - depends on service type

Digital services to consumers anywhere: Standard-rated (9% GST) if your turnover exceeds threshold

Complex area. Get advice for your specific situation if serving overseas customers regularly.

Quick Recap: GST Filing Checklist

You now know how to file GST returns in Singapore. Here's your quick reference checklist.

Before You Start Filing

Documents ready:

[ ] All sales invoices for the quarter (including deposits)
[ ] All purchase invoices with proper tax invoice format
[ ] Bank statements reconciled
[ ] Export permits (if claiming zero-rating)
[ ] Import permits (if claiming import GST)
[ ] Credit notes issued and received

Information calculated:

[ ] Total standard-rated sales (excluding GST)
[ ] Total zero-rated sales (if any)
[ ] Total output tax collected
[ ] Total claimable input tax paid
[ ] Revenue figure from profit & loss

Access:

[ ] CorpPass or Singpass credentials
[ ] 30-60 minutes uninterrupted time

Filing Deadlines (Mark Your Calendar)

Q1 (Jan-Mar): Due 30 April
Q2 (Apr-Jun): Due 31 July
Q3 (Jul-Sep): Due 31 October
Q4 (Oct-Dec): Due 31 January (following year)

Reminder: Set alerts 2 weeks before each deadline.

The Filing Process

Step 1: Log in

Go to mytax.iras.gov.sg
Use CorpPass (companies) or Singpass (sole proprietors)
Navigate to "File GST Return (F5)"

Step 2: Select correct quarter

Verify accounting period dates
Check deadline shown

Step 3: Fill main boxes

Box 1: Standard-rated supplies (excluding GST)
Box 2: Zero-rated supplies (if any)
Box 3: Exempt supplies (usually $0)
Box 4: Auto-calculated (1+2+3)
Box 5: Taxable purchases (excluding GST)
Box 6: Output tax (GST collected)
Box 7: Input tax (GST claimable)
Box 8: Net GST (auto-calculated: 6-7)

Step 4: Fill additional boxes

Box 9-12: Special schemes (most SMEs: not applicable)
Box 13: Revenue (from profit & loss)
Box 14-17: Digital/platform supplies (most SMEs: select "No")

Step 5: Review

Box 6 roughly equals Box 1 × 9%?
Box 7 looks reasonable for your purchases?
All foreign currency converted to SGD?
No obvious errors?

Step 6: Submit

Tick declaration
Click Submit
Save confirmation (reference number, amount owed/refunded)

Step 7: Pay (if Box 8 positive)

GIRO, internet banking, or myTax Portal
Must pay by same deadline as filing

Common Mistakes to Avoid

Don't include GST in Box 1 or Box 5

Wrong: Invoice $10,900 including GST → enter $10,900
Correct: Invoice $10,900 including GST → enter $10,000

Don't claim disallowed input tax

Motor cars (purchase, fuel, maintenance)
Club subscriptions
Medical expenses (with exceptions)
Entertainment without documentation
Family benefits

Don't forget timing of supplies

Deposits: Declare when received (not when final invoice)
Progress billing: Declare each invoice as issued
Credit notes: Reduce quarter when issued

Don't claim zero-rating without documentation

Need export permit for goods
Need customer location proof for services

Don't calculate Box 6 from Box 1

Track output tax separately (rounding differences)

Don't calculate Box 7 from Box 5

Track input tax separately

Key Figures to Remember

Penalties:

Late filing first offense: $200
Late filing repeat offense: $1,000-$5,000
Late payment (>60 days): 5% of unpaid GST
Self-correction threshold: $3,000 net GST error

Time limits:

Pre-registration claims: Up to 6 months before registration
Bad debt relief: Minimum 6 months after due date
Supplier payment: Must pay within 12 months or repay input tax
Record keeping: 5 years

GST rate: 9% (as of 1 January 2024)

After Filing

If you owe (Box 8 positive):

[ ] Pay by deadline
[ ] Verify payment processed
[ ] Save payment confirmation

If refund (Box 8 negative):

[ ] Wait 4-6 weeks for standard refunds
[ ] Respond promptly to any IRAS queries
[ ] Verify bank account on file is correct

Every quarter:

[ ] Check myTax Portal for correspondence
[ ] File on time (no exceptions)
[ ] Keep all records organized

When to Get Help

Get professional help immediately if:

[ ] Already missed deadlines
[ ] Facing IRAS queries or audit
[ ] Dealing with exports/imports regularly
[ ] Partially exempt business
[ ] High transaction volume (>100/month)
[ ] Made errors in past returns
[ ] Don't have time for quarterly filing
[ ] Want tax optimization advice

Cost of professional help: $1,000-1,600/year (GST only) or $7,000-15,000/year (full bookkeeping)

Cost of DIY errors: One mistake can cost $2,000-15,000 in penalties and corrections

Quick Reference: Box Summary

Box	What It Is	Most SMEs
1	Standard-rated sales (excl GST)	✓ Always use
2	Zero-rated sales	If exporting
3	Exempt sales	Usually $0
4	Total supplies (auto)	✓ Always use
5	Taxable purchases (excl GST)	✓ Always use
6	Output tax	✓ Always use
7	Input tax	✓ Always use
8	Net GST (auto)	✓ Always use
9	Special schemes	Rarely
10-12	TRS/bad debt/pre-reg	As applicable
13	Revenue	✓ Always use
14-17	Digital/platform	Usually "No"

Resources

IRAS official guidance:

Our articles:

Professional help:

Monthly Bookkeeping Service - Includes GST filing
Corporate Tax Filing
Company Secretary

Save this checklist. Refer to it before each quarterly filing.

Better yet: Let us handle it for you. Never worry about GST filing deadlines again.

Making Your Decision: What's Next

You've reached the end. You now understand the complete GST filing process: every box, every deadline, every condition, every complexity.

The question: What will you actually do?

The Reality Check

Filing GST correctly requires:

1.5-2 hours per quarter (if organized)
5-10 hours per quarter (if messy records)
Understanding of 15+ boxes
Knowledge of time of supply rules
Proper classification of standard/zero/exempt
Documentation of export/import transactions
Reverse charge calculations
Input tax claiming conditions
Partial exemption apportionment (if applicable)
Currency conversions
Adjustment mechanisms

Miss one detail: IRAS query.

Get multiple things wrong: Audit.

Persistent errors: Penalties of $5,000-15,000+.

What Most Business Owners Do Wrong

Mistake 1: Thinking it's simple

"Just fill in some boxes, how hard can it be?"

Then they discover timing rules, apportionment requirements, and disallowed input tax. By the time they realize it's complex, they've already filed incorrectly.

Mistake 2: Treating it as annual task

Filing quarterly but only organizing records once a year doesn't work. You end up scrambling to reconstruct three months of transactions in the last week before deadline.

Mistake 3: Focusing on cost, not value

"I'll save $10,000/year by doing it myself."

But they spend 40 hours (worth $6,000), make errors costing $3,000 in penalties, and miss $4,000 in tax optimization. Net result: Lost $3,000 trying to "save" $10,000.

Mistake 4: Hiring cheapest option

$3,000/year accountant who's disorganized, slow to respond, and makes errors. You still chase them for updates, fix their mistakes, and deal with IRAS queries they should handle.

Cheap accounting is expensive accounting.

The Professional Approach

After years working on statutory audits at KPMG and Deloitte, I understand Singapore compliance. The businesses that succeed treat compliance as operational infrastructure, not a cost to minimize.

What professional GST filing actually includes:

Monthly record review:

Transactions classified correctly (standard/zero/exempt)
Input tax claims verified (not just "if there's GST, claim it")
Documentation maintained (export permits, proper tax invoices)
Issues caught early (not discovered at filing deadline)

Quarterly GST filing:

All boxes calculated accurately
Timing of supplies handled correctly
Currency conversions done properly
Special cases addressed (bad debt, credit notes, adjustments)
Filed on time, every time

IRAS correspondence:

Queries answered professionally
Documentation provided promptly
Audits handled with expertise
You don't deal with IRAS directly (we do)

Tax optimization:

Legitimate expense claims maximized
Timing strategies for revenue/expenses
Relief schemes applied
Saves $2,000-7,000/year typically

Peace of mind:

Zero time spent on GST filing
Zero stress about deadlines
Zero penalties
Someone to call with questions

What Makes Us Different

Big 4 technical expertise: I bring statutory audit experience from KPMG and Deloitte. Technical accuracy that prevents penalties and withstands IRAS scrutiny.

Actually responsive: WhatsApp or call, get response within 24 hours (often within 1 hour). No "sorry, we're busy during tax season" or waiting 3-5 days for email replies.

Transparent pricing: Everything upfront, no hidden fees. You know exactly what you're paying before engaging us.

Proactive compliance: We track your deadlines, remind you weeks in advance what's needed, and file on time. You never worry about missing a deadline.

Our Services

Monthly Bookkeeping Service

Comprehensive monthly service including:

Complete bookkeeping (all transactions recorded)
Bank reconciliation
Monthly financial reports
Quarterly GST filing (all 4 quarters)
Annual corporate tax filing
ECI filing
IR8A filing for employees
ACRA annual return
All compliance tracked

Pricing: $7,000-15,000/year

Low volume (<50 transactions/month): $7,000-8,000/year
Medium volume (50-150 transactions/month): $10,000-12,000/year
High volume (150+ transactions/month): $13,000-15,000/year

Best for: Most SMEs who want complete compliance handled professionally.

Corporate Tax Filing Service

If you're handling GST yourself but need help with:

ECI filing
Form C-S / Form C preparation
Tax optimization
Corporate tax filing

Pricing: Part of yearly compliance packages ($1,500-3,000/year)

Company Secretary Service

ACRA compliance:

Annual return filing
Financial statements (XBRL)
Company particulars updates
Statutory registers

Pricing: Included in monthly packages or standalone from $300-800/year

Company Incorporation

Starting new business? We set up proper compliance from day one:

Company registration
GST registration (if needed)
Accounting system setup
Compliance calendar

So you never fall behind.

Stop Wrestling With GST Filing

You've spent time reading this guide. You now understand how complex GST filing actually is.

The question: Is this the best use of your time?

Your time is worth $100-500/hour. Spending 20-40 hours/year on GST filing = $2,000-20,000 in lost revenue opportunity.

Professional service costs $7,000-15,000/year and saves:

Penalties avoided: $1,000-5,000/year
Tax optimization: $2,000-7,000/year
Your time freed up: 50-80 hours/year

Net benefit: $3,000-10,000/year positive return.

Plus you actually sleep at night.

What Happens Next

Step 1: WhatsApp or call us

Tell us about your business:

Revenue level
Transaction volume
Current situation (filing yourself, have accountant, behind on filings)
What help you need

Step 2: We'll quote you a fixed price

Based on your complexity:

Number of transactions
Special situations (exports, imports, reverse charge)
Catch-up work needed (if behind)

No surprises. Everything upfront.

Step 3: We take over

Access your records
Get everything caught up (if needed)
Set up systems
Handle all future filings

You focus on running your business.

Ready to Stop Worrying About GST?

Common questions we answer:

"How much will this cost for my business?"
"Can you help me catch up on missed filings?"
"I'm behind on 3 quarters, what do I do?"
"My current accountant is disorganized, can you take over?"
"How quickly can you start?"

One conversation could save you $5,000-15,000 in penalties this year.

Still Have Questions?

Our expert team is ready to help.

Chat on WhatsApp

Last updated: October 2025. Filing procedures based on current myTax Portal interface. IRAS may update processes - always verify current requirements at iras.gov.sg.

GST Filing in Singapore: Step-by-Step Guide to F5 Form [2025]

Table of Contents

GST Filing Basics: What You're Actually Filing

Before You Start: What You Need Ready

Documents You Must Have

Information You Need to Calculate

Software vs Manual Calculation

Cut-Off Procedures

Checklist Before You Start Filing

Understanding the F5 Form: Complete Box Breakdown

The Main Boxes (1-8)

Additional Boxes (9-17)

Summary: Which Boxes Most SMEs Use

Step-by-Step: Filing F5 via myTax Portal

Before You Start

Access myTax Portal

Select Accounting Period

Fill the Main Boxes

Fill Additional Boxes

Review Before Submitting

Submit

Make Payment (If Box 8 Positive)

After Submission

Standard-Rated Supplies: The Complexities

Time of Supply Rules: When to Declare

Deposits and Advance Payments

Mixed Supplies: Standard-Rated and Zero-Rated

Partially Exempt Businesses

Vouchers, Discounts, and Rebates

Related Party Transactions

Deemed Supplies

Change of Use

Foreign Currency Transactions

Key Takeaway

Input Tax Claims: Conditions and Restrictions

The Attribution Test: Core Requirement

Partial Exemption: Input Tax Apportionment

The 12-Month Payment Rule

Proper Tax Invoice Requirements

Motor Vehicle Restrictions: Detailed Rules

Entertainment Restrictions: When You CAN Claim

Reverse Charge: Double Entry Explained

Capital Goods Scheme: Long-Term Assets

Key Takeaway

Special Cases and Adjustments

Bad Debt Relief: Claiming Back Output Tax

Credit Notes: Adjusting Previous Declarations

Import GST: Claiming on Goods Brought In

Adjustments to Previous Returns: Small Errors

Pre-Registration Input Tax Claims

Voluntary Disclosure of Errors

When to Seek Professional Help

Additional Complexities and Edge Cases

Foreign Currency Transactions

Export Documentation Requirements

Amended Returns Process

Mixed Supply Complexities

Reverse Charge Edge Cases

Electronic Marketplace and Platform Supplies

When It Gets Too Complex

After Filing: What Happens Next

Payment Process (If You Owe GST)

Refund Process (If IRAS Owes You)

IRAS Queries and Correspondence

GST Audits

Record Keeping Requirements

Compliance Tips

DIY vs Professional Help: The Real Cost

Time Cost of DIY Filing

Risk Cost of DIY Errors

Professional GST Filing Costs

The Real Comparison

When DIY Makes Sense

When to Hire Professional Help

What About Accounting Software?

The Bottom Line

Frequently Asked Questions

Quick Recap: GST Filing Checklist

Before You Start Filing

Filing Deadlines (Mark Your Calendar)