GST InvoiceNow Requirements in Singapore: Which Businesses Are Affected?
TABLE OF CONTENTS
- 1. What the GST InvoiceNow requirement means
- 2. Which businesses are affected, and from when
- 3. How to work out which phase you are in
- 4. Who is excluded, and what won't get you out
- 5. What you actually send to IRAS
- 6. Cost, free software and grants
- 7. What happens if you don't comply
- 8. What to do before your date
If you think InvoiceNow is a 2031 problem, check your numbers first. That date is real, but it only applies to the largest GST-registered businesses. If your total annual supplies are S$200,000 or less, the GST InvoiceNow requirement reaches you on 1 April 2028. New voluntary GST registrants are already covered.
Smaller businesses go first by design. IRAS says they can use InvoiceNow-ready accounting software and onboard with minimal cost and effort, while larger businesses need time to fit the change into their IT refresh cycles.
This guide covers who the requirement applies to, how to work out your phase, who is excluded, and what to sort out before your date. It reflects IRAS’s FAQ published on 23 September 2026.
What the GST InvoiceNow requirement means
The GST InvoiceNow requirement is an IRAS rule that makes GST-registered businesses send their invoice data directly to IRAS through the InvoiceNow network, using an IMDA-accredited InvoiceNow-Ready Solution. It is being phased in by registration type and business size. Every GST-registered business except a small excluded group must be on board by 1 April 2031.
InvoiceNow is Singapore’s national e-invoicing network, built on the Peppol standard. In practice, your accounting software creates the invoice and a copy of the data reaches IRAS through an accredited Access Point Provider. IRAS says the data should mean faster GST audits and quicker refunds, plus built-in checks that reduce the chance of being wrongly charged GST.
Which businesses are affected, and from when
IRAS has set six start dates. The first two are already live.
| Applies from | Who is covered |
|---|---|
|
1 Nov 2025 |
Newly incorporated companies (incorporated within 6 months of applying) that apply for voluntary GST registration |
|
1 Apr 2026 |
Any business that applies for new voluntary GST registration, whatever its incorporation date or structure |
|
1 Apr 2028 |
All new compulsory GST registrants, and existing GST-registered businesses with total annual supplies of S$200,000 or less |
|
1 Apr 2029 |
Existing GST-registered businesses with total annual supplies of up to S$1 million |
|
1 Apr 2030 |
Existing GST-registered businesses with total annual supplies of up to S$4 million |
|
1 Apr 2031 |
Existing GST-registered businesses with total annual supplies above S$4 million |
Source: IRAS, GST InvoiceNow Requirement and the IRAS FAQ, version 23 September 2026.
Read the bands as cumulative. A business with S$600,000 in annual supplies sits in the 1 April 2029 group, because the 2028 group already takes everyone at or below S$200,000.
New founders should watch one trap. If you apply for compulsory registration on a forecast of S$1 million in taxable turnover but cannot back that forecast with enough documents, IRAS can register you on a voluntary basis instead. IRAS’s FAQ confirms the business must then comply with InvoiceNow. If you are still setting up, how Singapore company registration works covers the incorporation side before GST enters the picture.
How to work out which phase you are in
If you were GST-registered before 2026, your phase depends on your total annual supplies. IRAS says it has notified these businesses of their implementation date from mid-2026, so look for that notice first. If you can’t find it, calculate it yourself.
IRAS’s method is to add up your standard-rated, zero-rated and exempt supplies across every prescribed accounting period that ends in calendar year 2025. If your GST periods don’t line up with the calendar year, the 12 months you use shift:
- Periods ending in March, June, September or December: January to December 2025
- Periods ending in January, April, July or October: November 2024 to October 2025
- Periods ending in February, May, August or November: December 2024 to November 2025
One result catches people out. Nil returns still count as returns filed, so a GST-registered company with no sales has total annual supplies of S$0 and lands in the 1 April 2028 group. Dormant and early-stage companies that kept their GST registration are first in line, not last.
If your periods are irregular or your supplies are mixed, get the calculation checked. Our GST compliance and filing support team can confirm your phase before you commit to a software plan.
Who is excluded, and what won't get you out
IRAS excludes two groups: overseas entities, and businesses registered for GST wholly because of the reverse charge regime. That carve-out is narrow. A business that is registered under the normal rules and also handles reverse charge transactions is still covered.
Three assumptions that don’t hold, according to IRAS:
- Being small or low volume. IRAS says these businesses must still comply and points them to free or low cost software instead.
- Selling only to related companies. No exemption applies.
- Making only zero-rated or exempt supplies. IRAS still needs invoice data on standard-rated and zero-rated purchases to back up your input tax claims.
What you actually send to IRAS
Two kinds of data go to IRAS: your sales invoices and your purchase invoices. On purchases, IRAS wants the standard-rated and zero-rated invoices that support your GST return. If you choose not to claim input tax on a supplier invoice, that invoice falls outside the requirement. Credit notes go in too.
Your customer’s status doesn’t change this. You send the data whether the customer is GST-registered, unregistered or not on InvoiceNow at all. When the customer isn’t on the network, your software extracts the data and sends it to IRAS separately. Customer name, UEN and address are mandatory fields, and invoice data that is missing them is rejected automatically. For retail and F&B, point-of-sale sales and petty cash purchases can be aggregated before sending.
Peppol invoices sent through the network reach IRAS in near real time. Data your software sends in batches must arrive by the earlier of the day you file the relevant GST return and its due date.
WORTH KNOWING
IRAS’s own pilot flagged poor data quality, inconsistent GST category codes, duplicate submissions and incomplete transmission. The first two start in your books, not the software. IRAS will accept legitimate differences between your invoice data and your GST return, such as timing differences or partly claimed input tax, but only if you can produce records that explain them. If your books can’t explain a gap, that leniency doesn’t help you. Clean ledgers carry more weight now, so it is worth fixing the most common bookkeeping mistakes SMEs make before your date, not after.
Cost, free software and grants
IRAS says InvoiceNow-ready software makes up the vast majority of accounting solutions, so for many SMEs this is a feature to switch on rather than a system to buy. According to IRAS’s FAQ, free-of-charge InvoiceNow-ready software is available for SMEs until March 2031, a new grant of up to S$1,000 will help SMEs with transition costs, and the Productivity Solutions Grant can cover up to 50% of eligible software subscription costs. A grant of up to S$5,000 is planned for larger businesses that adopt early. IRAS says details of the new grants will follow, so confirm current terms with your provider before you budget around them.
If your software isn’t on IMDA’s accredited list, IRAS gives three routes: connect it through an accredited Access Point Provider, move to a free-of-charge package, or switch to an InvoiceNow-ready product. If an accountant or billing provider issues your invoices, they can submit through their own InvoiceNow-ready software with your consent. So ask your outsourced bookkeeping support provider which platform they use and who handles the submissions.
What happens if you don't comply
IRAS’s FAQ doesn’t set out a penalty table, but it is clear on consequences. A business that registered for GST voluntarily from 1 November 2025 may have its application rejected or its registration revoked if it doesn’t comply. For everyone else, IRAS says its enforcement will be calibrated in the early phases for genuine mistakes that aren’t negligent, but action may be taken against non-compliant businesses.
Also, nothing here replaces your existing duties. You still file GST returns on time and keep business and accounting records, including source documents, for at least five years.
What to do before your date
Work through these in order. Steps 1 and 2 take an afternoon.
- Confirm your phase. Find IRAS’s notice or run the total annual supplies calculation above.
- Check your software against IMDA’s list of InvoiceNow-Ready Solution Providers. If it isn’t there, pick one of the three routes above.
- Register on the InvoiceNow network through your solution provider and test. IRAS has offered a test sandbox since September 2024, which your provider can use.
- Clean your master data. Collect customer names, UENs and addresses, and map your internal tax codes to IRAS’s GST category codes. You can keep your own codes if you map them.
- Agree who sends what. Decide whether your team or your accountant submits sales and purchase data, and get consent in writing.
- Consider going early. IRAS strongly encourages it, and existing businesses that haven’t switched the feature on simply have their Peppol invoices go to customers as usual, without a copy reaching IRAS. Early adopters get time to fix teething problems.
Conclusion
For GST-registered businesses with annual supplies of S$200,000 or less, the GST InvoiceNow requirement is a 2028 deadline, not a 2031 one, and for new voluntary registrants it is already live.
Three things to take from this. Work out your phase from your total annual supplies, not from a date you assumed. Check your software now, because free and low cost routes exist. And keep your records tight, because IRAS will accept explainable differences between your invoice data and your return only if your books can explain them.
Book a free 30-minute consultation with a BSH accounting professional. Bring your last four GST returns and the name of your accounting software, and we’ll confirm your phase and review whether your current setup is ready. This guide is general information, not professional tax advice, so your own circumstances may differ.
Not sure which InvoiceNow phase applies to you?
Speak to the BSH Group team about your GST position and software readiness before your date arrives.
Frequently Asked Questions
What is the GST InvoiceNow requirement in Singapore?
It is an IRAS requirement for GST-registered businesses to send invoice data directly to IRAS through the InvoiceNow network, using an InvoiceNow-Ready Solution. It is phased in by registration type and business size, and it doesn’t replace GST returns or record keeping. Only overseas entities and businesses registered wholly because of the reverse charge regime are excluded.
When does InvoiceNow become mandatory for existing GST-registered businesses?
It depends on your total annual supplies. IRAS has set 1 April 2028 for existing businesses with supplies of S$200,000 or less, 1 April 2029 for up to S$1 million, 1 April 2030 for up to S$4 million and 1 April 2031 for those above S$4 million. IRAS says it has notified businesses registered before 2026 of their dates.
Can small businesses be exempted from InvoiceNow in Singapore?
No. IRAS’s FAQ says small businesses, low-volume businesses, businesses that supply only related entities and businesses that make only zero-rated or exempt supplies must still comply. For smaller businesses, IRAS points to free or low cost InvoiceNow-Ready software instead.
How much does it cost to adopt InvoiceNow?
IRAS says free-of-charge InvoiceNow-ready software is available for SMEs until March 2031, and most accounting solutions are already InvoiceNow-ready. A new grant of up to S$1,000 is planned for SME transition costs, and the Productivity Solutions Grant can cover up to 50% of eligible software subscription costs. Confirm current terms with your provider, since IRAS has said details will follow.
Do I still need to file GST returns and keep records under InvoiceNow?
Yes. The requirement sits on top of your existing GST duties. You must keep proper business and accounting records, including source documents, for at least five years, and store electronic tax invoices in a form that lets IRAS verify your returns. IRAS can still ask for the underlying invoices during an audit.