Most business owners in Singapore meet GST for the first time when turnover starts climbing and someone asks whether the company should be charging 9 per cent. GST registration in Singapore is compulsory for some businesses and optional for others, and the distinction matters a great deal. Register late and you may owe IRAS the GST you never collected. Register voluntarily without thinking it through and you have signed up for at least two years of quarterly filing you did not need.
This article explains when GST registration in Singapore becomes compulsory, when voluntary registration is worth the trouble, and how the application works through the IRAS myTax Portal.
Who this applies to
GST registration applies to the business entity, not to the individual trade or the person running it. That means the following are all potentially liable to register:
- Private limited companies incorporated with ACRA
- Sole proprietorships and partnerships
- Limited liability partnerships and limited partnerships
- Branches of foreign companies making supplies in Singapore
- Overseas suppliers of digital and low-value goods to Singapore consumers, under the Overseas Vendor Registration regime
One point catches out sole proprietors. If the same individual runs two or three separate sole proprietorships, IRAS looks at their combined taxable turnover, because they are all the same legal person. Two businesses each turning over S$600,000 put that owner over the threshold, even though neither comes close on its own.
Key rules and requirements in Singapore
The governing legislation is the Goods and Services Tax Act 1993, administered by IRAS. The prevailing GST rate has been 9 per cent since 1 January 2024.
The S$1 million threshold and the two tests
Compulsory registration is triggered by taxable turnover of more than S$1 million, tested two ways:
- The retrospective view. Your taxable turnover for the past calendar year exceeded S$1 million. If so, you apply between 1 and 30 January and your registration takes effect on 1 March of that year.
- The prospective view. You can reasonably expect taxable turnover to exceed S$1 million over the next 12 months, for example because you have signed contracts that make it a near certainty. If so, you apply within 30 days of forming that expectation.
Either test on its own creates the obligation. The prospective test is the one businesses forget, because it depends on your own forecast rather than on a figure already in the accounts.
What counts as taxable turnover
Taxable turnover is not the same as revenue in your profit and loss statement. It covers standard-rated supplies (9 per cent) and zero-rated supplies such as exports and international services. It excludes exempt supplies, broadly most financial services, the sale and lease of residential property, investment precious metals and certain digital payment token transactions. It also excludes out-of-scope supplies, such as sales of goods that never enter Singapore. Getting this classification wrong is the most common reason a business registers unnecessarily, or registers late.
Voluntary registration and its conditions
If you are below the threshold you may still apply voluntarily, provided you are making or intend to make taxable supplies. IRAS attaches conditions:
- The director, sole proprietor, partner or person preparing the GST returns generally has to complete the IRAS “Overview of GST” e-Learning course and pass the quiz, unless the business is under a qualified tax agent
- GIRO must be set up for GST payment and refunds
- You must remain registered for at least two years, and must start making taxable supplies within two years if you have not already
- Businesses applying for voluntary registration from 1 April 2026 fall under the GST InvoiceNow Requirement and must transmit invoice data to IRAS through the Peppol network. Newly incorporated companies, meaning those applying within six months of incorporation, have been subject to this since 1 November 2025
Step-by-step process
- Calculate your taxable turnover properly. Strip out exempt and out-of-scope supplies, then run the figure for the past calendar year and for your forward 12-month forecast.
- Determine which test you fall under, if any, and diarise the deadline. January for retrospective, 30 days from your forecast for prospective.
- Decide on voluntary registration if you are under the threshold, weighing input tax recovery against the compliance burden and the two-year lock-in.
- Get the prerequisites in place. Corppass access for the person filing, the e-Learning certificate where required, a GIRO application, and an InvoiceNow-ready invoicing system if the requirement applies.
- Submit Form GST F1 through the IRAS myTax Portal, with supporting documents such as your ACRA business profile and evidence of turnover or signed contracts.
- Wait for the notification of registration, confirming your GST registration number and effective date. IRAS typically takes around 10 working days for straightforward applications.
- Update your systems before the effective date. Invoice templates need the GST registration number and a GST line, quotes and contracts need reviewing, and accounting software needs the correct tax codes.
- File your GST F5 returns, usually quarterly, within one month of the end of each accounting period, with payment due at the same time.
Common mistakes to avoid
- Using total revenue instead of taxable turnover. A property company with substantial residential rental income may be nowhere near the threshold once exempt supplies come out.
- Ignoring the prospective test. Winning a large contract in July can put you over the line long before the calendar year ends.
- Missing the application window. IRAS can backdate your effective date, leaving you to account for GST on sales already made at prices that never included it.
- Charging GST before the effective date. Collecting tax you are not yet registered to collect is an offence, and the amounts are recoverable by IRAS.
- Registering voluntarily to look larger. The two-year commitment, quarterly filing and the effective price increase to non-GST-registered customers are real costs.
- Weak records. Tax invoices, import permits and accounting records must be kept for at least five years, and input tax claims depend on valid supporting documents.
Practical examples
A consultancy that crosses the line quietly. A firm bills S$1.08 million in a calendar year. It is over the threshold on the retrospective test and must apply by 30 January, with registration effective 1 March. It has roughly six weeks to notify clients and reprice.
An exporter that benefits from voluntary registration. A trading company sells almost entirely to overseas buyers, so its supplies are zero-rated. Turnover is S$400,000, and there is no obligation to register. Registering voluntarily lets it recover input GST on local purchases and freight while charging customers nothing, putting it in a net refund position.
A retailer better off staying out. A shop turning over S$500,000 sells mainly to individuals. Registering would add 9 per cent to shelf prices or eat into margin, with modest input tax to recover. Staying unregistered until it nears the threshold is the more sensible position.
How a corporate secretary can help
A corporate secretary in Singapore sits close to the statutory record and is often the first to see that turnover or business activity has shifted in a way that carries a tax consequence. Working alongside an accounting and tax team, the practical support usually covers monitoring taxable turnover against the threshold, preparing and lodging the GST F1 application, arranging GIRO and Corppass access, aligning invoice templates and contract wording with the effective date, and taking on the quarterly GST F5 filing once registration is live.
Raffles Corporate Services assists clients with ACRA filings, corporate secretarial work, bookkeeping, GST and corporate tax compliance and payroll, so the registration decision can be weighed alongside the rest of the company’s obligations rather than in isolation.
Frequently Asked Questions
Can I register for GST before I have any sales?
Yes, under voluntary registration, provided you can show a genuine intention to make taxable supplies, for example through signed contracts, a business plan or purchase commitments. IRAS may ask for a guarantee, and you must begin making taxable supplies within two years.
What happens if I register late?
IRAS will backdate the effective date to when you were required to register. You remain liable for the GST that should have been charged from that date, whether or not you collected it from customers, and penalties may apply. Voluntary disclosure generally results in more lenient treatment.
Can I deregister once turnover falls?
Yes. If taxable turnover for the past 12 months is S$1 million or less and is not expected to exceed it in the next 12 months, you may apply to cancel your registration. Voluntary registrants must have completed two years first. Cancellation is also compulsory when the business ceases to make taxable supplies.
Does the GST InvoiceNow Requirement apply to everyone?
Not yet. It is being phased in, starting with newly incorporated voluntary registrants from 1 November 2025 and extending to all new voluntary registrants from 1 April 2026. Existing GST-registered businesses are outside the mandate for now, though many adopt InvoiceNow early.
Key takeaways
- GST registration becomes compulsory once taxable turnover exceeds S$1 million on either the retrospective or the prospective test
- Taxable turnover excludes exempt and out-of-scope supplies, so it is usually lower than headline revenue
- Retrospective cases apply in January for a 1 March effective date. Prospective cases apply within 30 days of forming the expectation
- Voluntary registration suits exporters and businesses selling to GST-registered customers, and rarely suits consumer-facing businesses with low input tax
- Voluntary registration carries a two-year minimum, GIRO, an e-Learning requirement and, from 1 April 2026, the GST InvoiceNow Requirement
- Late registration is backdated and the unbilled GST becomes your cost, so monitor turnover monthly rather than annually
Requirements may change, so always check the latest guidance from ACRA, IRAS or MOM, or consult a professional adviser.
If you would like to find out more about how Raffles Corporate Services can assist with your company’s compliance and corporate secretarial requirements, please get in touch with the team at [email protected].
Yours sincerely,
The editorial team at Raffles Corporate Services
Disclaimer: This does not constitute legal advice. If you require legal advice, please contact a lawyer.