InvoiceNow GST Requirement in Singapore: Who Must Comply, When and How to Get Ready

The InvoiceNow GST requirement makes GST-registered businesses in Singapore send a copy of their sales and purchase invoice data to IRAS through InvoiceNow-Ready accounting software. It already applies if you applied for voluntary GST registration on or after 1 April 2026, or from 1 November 2025 if your company applied within 6 months of incorporation. Other GST-registered businesses join in phases from 1 April 2028 to 1 April 2031.

Voluntary registrants have the most at stake: InvoiceNow is a condition of their registration, so IRAS can refuse or cancel it if they do not comply. Amounts below are in Singapore dollars (SGD), and the rules are as at November 2026.

Key takeaways

• Already in force for voluntary GST registrations applied for from 1 April 2026, and for companies that applied from 1 November 2025 within 6 months of incorporation.
• Existing registrants join by total 2025 supplies: $200,000 or less from 1 April 2028, up to $1 million from 1 April 2029, up to $4 million from 1 April 2030 and above $4 million from 1 April 2031.
• Deadline: each period's data must reach IRAS by the earlier of your GST F5 filing date and its due date.
• A Peppol ID is not enough: you need an accredited InvoiceNow-Ready solution, such as Xero, or your own ERP connected through an accredited Access Point, with GST submission switched on.
• Support: free packages until 31 March 2031 and a fixed $1,000 grant for qualifying smaller businesses.

Table of Contents

1. What Is InvoiceNow? Peppol E-Invoicing in Singapore Explained
2. GST InvoiceNow Timeline: Who Must Comply and When
3. What Invoice Data Must You Send to IRAS?
4. How Does InvoiceNow Affect Voluntary GST Registration?
5. How to Get InvoiceNow-Ready in 5 Steps
6. Is Your Accounting Software InvoiceNow-Ready?
7. What Does InvoiceNow Cost and Which Grants Can You Claim?
8. What Happens If You Do Not Comply?
9. Common InvoiceNow GST Mistakes to Avoid
10. When Should You Get Professional Help?
11. Frequently Asked Questions
12. Official Sources

What Is InvoiceNow? Peppol E-Invoicing in Singapore Explained

InvoiceNow is Singapore's nationwide e-invoicing network, launched in 2019 and managed by the Infocomm Media Development Authority (IMDA) as Singapore's Peppol Authority. Invoices travel in the international Peppol format from the supplier's accounting system straight into the customer's, so emailing a PDF is not e-invoicing. IMDA accredits the InvoiceNow-Ready Solution Providers (IRSPs) that sell compliant software and the Access Point Providers that route invoices. Your Peppol ID is your address on the network, listed in the SG Peppol Directory under your UEN.

The GST requirement copies IRAS in. Once your software's GST InvoiceNow submission feature is on, a Peppol invoice sent to a customer on the network reaches IRAS almost in real time. Everything else, including paper or PDF invoices to customers outside the network, POS sales and the purchase invoices you record, is extracted from your software and sent regularly, such as daily or weekly. Your customers do not need to be on InvoiceNow for you to comply.

GST InvoiceNow Timeline: Who Must Comply and When

Total annual supplies is Box 4 of your GST F5 (standard-rated, zero-rated and exempt supplies) across all accounting periods ending in 2025. Nil returns count as $0, which puts a registrant with no sales in the 2028 group. If those periods cover fewer than 365 days, scale up to a 365-day equivalent.

Example (hypothetical): Company A's four 2025 quarterly returns show Box 4 totals of $180,000, $210,000, $260,000 and $250,000, or $900,000 in all, so it joins on 1 April 2029. Company B registered on 1 July 2025, so its two 2025 returns cover only 184 days (July to December) and total $650,000. Its 365-day equivalent is $650,000 × 365 ÷ 184 = $1,289,402, so it joins on 1 April 2030.

IRAS began notifying businesses registered before 2026 of their dates from mid-2026 (those with no returns for periods ending in 2025 will be told later), and its GST InvoiceNow Requirement page has a date calculator. Overseas businesses with a section 33(1) local agent, OVR-registered overseas vendors and businesses registered only because of reverse charge are excluded, but a foreign company's Singapore branch is not. GST groups will be told their date later. The extension to all registrants came at Committee of Supply 2026 (see our Budget 2026 guide for SMEs); IRAS says the law for the later phases will follow, but plan on the published dates.

What Invoice Data Must You Send to IRAS?

Send the invoice data behind everything in your GST return, minus a short list of exclusions.

• In scope: standard-rated, zero-rated and exempt supplies, and standard-rated and zero-rated purchases. Documents include invoices, serially numbered receipts, debit notes and credit notes, but not sales orders, pro-forma invoices or statements of account.
• Not required: these include deemed supplies, reverse-charge transactions, exempt financial services, import permits, out-of-scope supplies, purchases from non-registered suppliers or with blocked input tax (such as motor car costs), pre-registration claims and bad debt relief.
• Totals allowed: only POS sales, sales with simplified tax invoices or receipts, and petty cash purchases such as staff claims can be aggregated; everything else goes invoice by invoice. Online sellers should also read our e-commerce seller accounting and GST guide.
• Customer details: invoices sent individually need the customer's UEN, name and address (an overseas registration number for a foreign customer, or "NA" for an individual).

This applies whether or not your customer is GST-registered, and even when no invoice is issued, such as related-company recharges settled by offset.

When Is the Invoice Data Due?

By the earlier of the date you file the GST return covering the transaction and that return's due date, one month after the period ends. Example (hypothetical): a 20 March 2027 invoice falls in the January to March return, due 30 April 2027. If you file on 20 April, its data is due by 20 April; if you file late on 15 May, it was still due by 30 April.

Does InvoiceNow Replace the GST F5?

No. You still file and pay within one month after each period, and a late F5 still costs $200 immediately plus $200 for each completed month, up to $10,000. What changes is the order of work: record, transmit, check, reconcile, then file. Our GST F5 guide covers the boxes themselves.

IRAS expects the data to match your return but accepts legitimate differences, such as timing, deemed supplies, reverse charge, apportioned or unclaimed input tax, and errors corrected in a later F5 instead of an F7. You will not be penalised for these if you keep proper records, including Peppol XML files, for at least 5 years and can produce them on request.

How Does InvoiceNow Affect Voluntary GST Registration?

Voluntary registration already came with conditions, such as completing IRAS's Overview of GST e-learning course before applying (unless exempt), setting up GIRO and staying registered for at least 2 years. IRAS's conditions for voluntary registration now list InvoiceNow alongside them, with the force of law.

The rule covers every voluntary application made on or after 1 April 2026, including re-registrations and compulsory applications approved only as voluntary because the $1 million forecast was not supported. The application date counts, not the approval date. Data is due from your effective registration date, and IRAS processes 60% of applications within 10 working days, so have the software and Peppol ID ready before you apply.

Pre-registration claims in your first return are not sent as invoice data, and the $1,000 grant is not open to voluntary registrations from 1 April 2026, so budget for the software. Still deciding? Read our guide on whether you need to register for GST, or let us handle the GST registration and set-up together. New companies can add both to their first-year compliance checklist.

How to Get InvoiceNow-Ready in 5 Steps

Start at least a quarter before your date. IRAS has welcomed early adopters since 1 May 2025.

1. Confirm your date. Check IRAS's letter or run its calculator on your 2025 Box 4 figures. For a new voluntary registration, it is your effective registration date.
2. Check your software against IMDA's list. If it is not listed, switch to a listed solution or a free package. On your own ERP, engage an IMDA-accredited Access Point Provider and allow 3 to 12 months.
3. Clean up your data. Add the UEN, name and address to every customer record, map your tax codes to IRAS's GST category codes and decide how POS sales, receipts and staff claims will be totalled. Purchase invoices must be in before each F5 is filed, so year-end catch-up bookkeeping no longer works.
4. Get a Peppol ID and switch on GST submission. Your software provider or Access Point registers your UEN in the SG Peppol Directory. Then activate the GST InvoiceNow submission feature, without which nothing reaches IRAS.
5. Test it and build it into your GST close. Check that each submission returns an IRAS acknowledgement ID, clear failures, reconcile to your draft F5 and only then file. Keep records, including Peppol XML files, for at least 5 years.

Is Your Accounting Software InvoiceNow-Ready?

The test is IMDA's list of accredited InvoiceNow-Ready Solution Providers, not a vendor saying it supports Peppol. A listed solution, whether an off-the-shelf package or an ERP from an accredited partner, can both exchange invoices on the network and send invoice data to IRAS. The version updated 12 October 2026 has 81 entries in its main table, with resellers listed separately. They include:

• Xero, under Xero (Singapore) Pte. Ltd.
• ABSS Accounting Connect and Premier Connect, AutoCount Accounting 2.0, Financio, SQL Account Version 5, Million Accounting, Sage 300 and Sage Intacct.
• SAP Business One, Microsoft Dynamics 365 Business Central and Odoo, through specific implementation partners, so check that your partner's version is listed.

Listings are for specific products and versions, and being listed means the software can comply, not that your organisation is set up. QuickBooks and Zoho Books do not appear in that version. If your package is missing, ask the vendor for a firm date, and time any switch for a quarter end or year end so balances carry across cleanly.

What Does InvoiceNow Cost and Which Grants Can You Claim?

For most small businesses the cost is a listed solution's subscription plus time to tidy customer records and tax codes; if you already use one, it may just mean switching a feature on, although some providers sell GST submission as an add-on or a higher plan, so check first. Support as at November 2026:

Check IMDA's InvoiceNow grants page and its grants FAQ before you buy. The $1,000 grant is for new subscriptions only, so renewals do not count, and businesses already subscribed to an InvoiceNow-Ready solution such as Xero are excluded even if they have never switched on GST submission (IMDA's answer is that they can simply turn it on). It also excludes free-package users, businesses that used any listed solution in the previous 3 months, voluntary registrations from 1 April 2026 and solutions funded by another government grant. IRAS treats the free package and all three grants as taxable. The Productivity Solutions Grant closed on 29 September 2026, and its replacement, the EDGE Grant, does not say whether InvoiceNow solutions qualify.

What Happens If You Do Not Comply?

For voluntary registrants the consequence is already set: IRAS may refuse the application or cancel the registration. Cancellation is not a tidy exit, because you file a final GST F8 and may have to account for GST on business assets you hold if those on which you claimed input tax are worth more than $10,000.

For the 2028 to 2031 phases, IRAS says enforcement action may be taken against non-compliant businesses. As at October 2026 it has published no penalty amount, and it says it will calibrate enforcement in the early phases for genuine mistakes that are not due to negligence. Your other GST obligations, and their penalties, are unchanged.

There is no opt-out. IRAS has said that small or low-volume businesses, businesses supplying only related entities and those making only zero-rated or exempt supplies must still comply. One published relief exists: a business on an ERP system shared across a commercial arrangement, such as a franchise group, can write to IRAS to ask for a later implementation date, which IRAS decides case by case.

Common InvoiceNow GST Mistakes to Avoid

• Treating a Peppol ID as compliance. Until the GST submission feature is on, nothing reaches IRAS.
• Sending sales but not purchases. Standard-rated and zero-rated purchases are in scope, including staff claims and card spend, which can go as totals.
• Expecting your Access Point to convert PDFs. It cannot; invoices must be recorded in your InvoiceNow-Ready software.
• Fixing errors the wrong way. A change in amount, such as an over-billing, needs a credit note, sent as separate invoice data. A fix that changes no amount, such as a corrected delivery address, is resubmitted under the original invoice's Document UUID, and IRAS uses the latest version.
• Filing the F5 before the data has gone. Data still queued on filing day is late.
• Assuming a free package does your accounting. IRAS calls the free packages basic e-invoicing; listed solutions range from simple invoicing tools to full accounting suites.

When Should You Get Professional Help?

You may not need paid help. If you already use a listed package such as Xero, your books are current and you mostly invoice local businesses, your provider's set-up guide and one carefully reconciled quarter may be enough.

Get help if you are registering voluntarily and need everything working from day one, have POS sales, petty cash or exempt supplies, run invoicing and accounts in separate systems, are behind on your books, or are weighing an ERP integration or grant claim. IRAS allows an accounting firm using a listed solution to process transactions for you, with your consent. Tax Filing SG is run by ex-Big 4 Singapore Chartered Accountants (ISCA members); see our accounting services, and we quote once we know your volumes and systems.

Frequently Asked Questions

Is InvoiceNow mandatory in Singapore?

For GST-registered businesses, yes, in phases. It already applies to voluntary registrations applied for from 1 April 2026, and to companies that applied from 1 November 2025 within 6 months of incorporation. Other registrants join between 1 April 2028 and 1 April 2031, and IRAS says the law for those phases will follow. Businesses that are not GST-registered do not have to use it.

When do GST-registered businesses need to use InvoiceNow?

It depends on the total supplies (Box 4) in your GST returns for periods ending in 2025: $200,000 or less from 1 April 2028, $1 million or less from 1 April 2029, $4 million or less from 1 April 2030 and above $4 million from 1 April 2031. New voluntary registrants start from their effective registration date instead.

What is an InvoiceNow-Ready solution?

It is accounting or finance software that sends and receives invoices on the InvoiceNow network and, through an IMDA-accredited Access Point, transmits invoice data to IRAS. It can be an off-the-shelf package from a provider on IMDA's accredited list or your own ERP system connected through an Access Point. Check IMDA's list before you buy or renew, because the software must send GST data to IRAS, not just Peppol invoices.

Does Xero support InvoiceNow?

Yes. Xero (Singapore) Pte. Ltd. is on IMDA's list of accredited InvoiceNow-Ready Solution Providers updated 12 October 2026. Being listed is not the same as being compliant, though: you still need to register your Peppol ID through Xero, switch on the GST InvoiceNow submission feature and map your tax rates correctly. Existing Xero subscribers cannot claim the $1,000 transition grant. Check the current steps with Xero or your Xero adviser.

Do I need InvoiceNow if I am not GST-registered?

No. The requirement applies only to GST-registered businesses, though you can join InvoiceNow voluntarily. Plan ahead if you expect to register: voluntary applications already carry the requirement from the registration date, and compulsory applications made from 1 April 2028 will too. Registration becomes compulsory once taxable turnover exceeds $1 million in a calendar year or is expected to over the next 12 months.

Is there a grant for InvoiceNow?

Yes. Businesses with total annual supplies of $4 million or less can claim a fixed $1,000 GST InvoiceNow Transition Grant for a new paid subscription to an accredited solution after 26 February 2026, activated before their mandate date, if they meet IMDA's other conditions. Existing subscribers, free-package users and voluntary registrations from 1 April 2026 are excluded. Larger businesses integrating their own ERP may get $5,000, plus $25,000 under the Queen Bee Grant if they qualify. All are taxable.

Official Sources

• IRAS: GST InvoiceNow Requirement (timeline, implementation date calculator and support)
• IRAS e-Tax Guide: Adopting GST InvoiceNow Requirement for GST-registered Businesses (Second Edition, 9 March 2026)
• IRAS: Frequently Asked Questions for GST InvoiceNow Requirement (version of 26 October 2026)
• IRAS e-Tax Guide: Conditions for GST Voluntary Registration
• IMDA: list of accredited InvoiceNow-Ready Solution Providers (updated 12 October 2026)
• IMDA: list of free-of-charge InvoiceNow packages for GST-registered businesses
• IMDA: InvoiceNow Grants
• IMDA: InvoiceNow grants FAQs (updated 4 November 2026)

About Tax Filing SG — We are a Singapore accounting practice run by ex-Big 4 Singapore Chartered Accountants (ISCA). We handle accounting, corporate tax, GST and company secretarial work for Singapore SMEs, including overdue and late filings.

Last updated: 9 November 2026. This article is general information based on IRAS and ACRA guidance as at November 2026, not advice for your specific situation. Rules, rates and deadlines change, so check the official sources above or speak to us before acting.