GST Registration Singapore 2026: When You Must Register & How

Introduction

Goods and Services Tax (GST) is Singapore’s broad-based consumption tax levied at 9% on the supply of taxable goods and services in Singapore, as well as on the importation of goods. Understanding when you must register for GST — and what happens if you miss the deadline — is one of the most critical compliance obligations for Singapore business owners in 2026.

This guide explains the GST registration thresholds, both compulsory and voluntary registration pathways, the step-by-step registration process, and the 2026 InvoiceNow requirements that apply to newly registered businesses.

The GST Registration Threshold: S$1 Million

You are legally required to register for GST in Singapore when your business’s taxable turnover exceeds — or is expected to exceed — S$1 million. IRAS applies two separate tests to determine whether the threshold has been crossed:

1. The Retrospective Basis

At the end of any calendar quarter (31 March, 30 June, 30 September, or 31 December), you must check whether your taxable turnover for the past 12 months has exceeded S$1 million. If it has, you must apply to register for GST within 30 days of the end of that quarter.

2. The Prospective Basis

At any point in time, if you have reasonable grounds to believe that your taxable turnover in the next 12 months will exceed S$1 million, you must register for GST within 30 days of forming that belief — regardless of your current turnover.

The 30-day registration window is strictly enforced. Failure to register on time means IRAS will backdate your registration to the correct effective date, and you will be liable to remit GST on all taxable sales made since that date — even if you did not collect GST from your customers. This can be a significant financial burden.

What Counts as “Taxable Turnover”?

Taxable turnover includes the total value of standard-rated and zero-rated supplies made in Singapore. It does not include:

• Exempt supplies (e.g., financial services, sale or lease of residential property)
• Out-of-scope supplies (e.g., supplies of goods located outside Singapore)
• Supplies made in your capacity as an employee
• Sale of capital assets not regularly supplied in the course of business

If your business makes primarily exempt supplies (such as a financial services firm), you may not be required to register even if your revenue exceeds S$1 million, as those supplies do not count towards the registration threshold. However, GST registered businesses making exempt supplies face input tax restrictions — seek professional advice if your business model involves exempt supplies.

Compulsory vs Voluntary GST Registration

Should You Register Voluntarily?

Voluntary GST registration makes sense for businesses that:

• Incur significant GST on purchases (rent, equipment, IT software, professional fees) and want to claim input tax credits
• Primarily supply to GST-registered businesses (B2B), where charging GST is not a competitive disadvantage as the customer can claim it back
• Are planning rapid growth and will likely hit the S$1 million threshold soon

Voluntary registration is generally not recommended for businesses that primarily sell to end consumers (B2C), as the 9% GST becomes an immediate price increase that competitors not registered for GST do not face.

There is a minimum 2-year registration period for voluntary registrants. You cannot deregister simply because business slows down — you must remain registered for at least 2 years.

How to Register for GST: Step-by-Step

1. Log in to myTax Portal at iras.gov.sg using your Corppass credentials.
2. Navigate to GST → “Register for GST.”
3. Select registration type: Compulsory or Voluntary.
4. Complete the application form: Enter business details, taxable turnover, expected supplies, and bank account information for GST refunds.
5. Upload supporting documents: ACRA business profile, financial records or projections, and evidence of taxable supplies.
6. Submit the application: IRAS typically processes GST registration applications within 10 working days.
7. Receive GST registration number: Once approved, IRAS will issue your GST registration number and confirm your effective registration date.

2026 InvoiceNow Requirement: What GST Registrants Need to Know

From 1 November 2025, all new voluntary GST registrants must use InvoiceNow-ready accounting software. From April 2026, this requirement extends to all new compulsory registrants. InvoiceNow is Singapore’s Peppol-based e-invoicing network, allowing businesses to send structured digital invoice data directly to customers’ accounting systems — and to IRAS for tax verification purposes.

Practically, this means newly registered businesses must ensure their accounting software (e.g., Xero, QuickBooks, MYOB, or other IRAS-approved software) is InvoiceNow-enabled before GST registration is complete. IRAS maintains a list of approved InvoiceNow-ready software on its website.

GST Filing Obligations After Registration

Once registered, you must:

• Charge 9% GST on all standard-rated supplies and display it on tax invoices
• File GST returns (F5) quarterly within one month of the end of each quarter
• Pay GST due by the same deadline as the return filing
• Keep records of all transactions for at least 5 years
• Issue tax invoices for all standard-rated supplies above S$1,000 to GST-registered customers

The quarterly GST filing deadlines in 2026 are 28 January, 28 April, 28 July, and 28 October. Late filing attracts a penalty of S$200 per month of delay, up to a maximum of S$10,000.

GST and Your Annual Compliance Obligations

GST registration does not replace your other tax obligations — it adds to them. Your company must still file its Estimated Chargeable Income (ECI), annual income tax return, and Annual Return with ACRA. For a complete overview of all filing deadlines, see our Important Compliance Requirements for Singapore Companies. For corporate income tax, see our Guide to Corporate Tax in Singapore.

GST registration also requires the maintenance of proper accounting records. A good corporate secretary will help track your filing obligations across all agencies — see Key Responsibilities of a Company Secretary in Singapore for more.

GST Deregistration

You may apply to deregister from GST if your taxable turnover has fallen below S$1 million and you do not expect it to exceed S$1 million in the next 12 months. For voluntary registrants, you must have been registered for at least 2 years. Deregistration must be applied for within 30 days of becoming eligible.

Conclusion

GST registration is a significant milestone in a Singapore business’s growth. Getting the timing right — registering on time to avoid backdated liabilities, and using InvoiceNow-ready systems from the outset — can save considerable time and money. Whether you are approaching the S$1 million threshold for the first time or considering voluntary registration to reclaim input tax, taking professional advice before you register is always worthwhile.

The team at Raffles Corporate Services provides GST registration assistance, ongoing GST filing support, and accounting services for Singapore companies. Contact us to ensure your GST compliance is properly managed from the very first day.

— The Editorial Team, Raffles Corporate Services