When Must an Online Seller Register for GST in Singapore?

The S$1 million GST threshold: two tests

IRAS's page Do I need to register for GST?/gst-registration-deregistration/do-i-need-to-register-for-gst) sets out two tests. You must register if either one applies.

For example, IRAS says a seller whose taxable turnover for 2025 exceeded S$1 million had to apply between 1 and 30 January 2026 and was registered from 1 March 2026. The two-month gap under the prospective test is a 2025 change: the Second Minister for Finance announced it on 28 February 2025 to give businesses time to start charging GST.

What counts as taxable turnover for an online seller

IRAS is clear that you look at taxable turnover, not total sales. Taxable turnover includes standard-rated supplies (local sales at 9%) and zero-rated supplies (exports and qualifying international services). It excludes exempt supplies, out-of-scope supplies and sales of capital assets such as equipment.

• Local orders delivered in Singapore count, whether sold through your own website or a marketplace.
• Overseas orders you ship out of Singapore count. They are zero-rated if you keep export evidence, but still count towards the S$1 million.
• Goods shipped from overseas to overseas (for example, a supplier ships straight to a foreign customer) are generally out of scope, per IRAS's e-commerce GST page/specific-business-sectors/e-commerce).
• Selling off old equipment does not count, as capital assets are excluded.

For a company, only that company's turnover counts, plus any sole proprietorships it owns. Partnerships combine businesses with the same partners.

The prospective test: what counts as a firm forecast

The prospective test catches growing sellers mid-year. IRAS says you need supporting documents for a forecast above S$1 million, such as signed contracts, accepted quotations, confirmed purchase orders, or income statements showing the past 12 months were already close to S$1 million and rising.

You do not have to register on a forecast based only on market assessments, business plans or sales targets. That matters for online sellers, because a projection in a pitch deck is not a trigger, but a signed wholesale contract with a retailer worth over S$1 million is.

Should you register for GST voluntarily?

You can register voluntarily below S$1 million. IRAS's factors to consider/gst-registration-deregistration/factors-to-consider-before-registering-voluntarily-for-gst) page and its e-Tax guide on voluntary registration conditions set out the trade-offs.

For a business-to-consumer online store, voluntary registration often costs more than it saves, because consumers cannot claim GST back. For a B2B seller or a business that imports a lot of stock, it can make sense. Our InvoiceNow set-up guide covers the InvoiceNow part.

What changes on your online store once registered

Registration changes your prices, invoices and accounting from the effective date.

1. 1

   Turn on GST in your store

   Set up the 9% rate for Singapore in Shopify or your platform. Our Shopify GST set-up guide walks through it.

2. 2

   Show GST-inclusive prices to consumers

   Prices shown to consumers must include GST. See our guide to GST-inclusive price display.

3. 3

   Issue proper tax invoices to business buyers

   GST-registered customers need tax invoices with your GST number. Our tax invoice requirements guide lists the fields.

4. 4

   Map GST in your accounting software

   Set GST codes in Xero or QuickBooks for local sales, exports, marketplace fees and purchases so the quarterly return is correct.

5. 5

   Keep export evidence

   To zero-rate overseas orders, keep the export documents IRAS requires, such as shipping records.

6. 6

   File GST returns on time

   GST returns are usually quarterly. Set reminders, and pay by GIRO if you registered voluntarily.

Late GST registration: what happens

IRAS treats GST as self-assessed: it will not remind you when you cross the threshold. If you register late, your registration is backdated to the date you should have been registered, and you must pay GST on past sales from that date, even if you did not charge customers. IRAS says you may also face a fine of up to S$10,000 and a penalty of 10% of the GST due.

If you apply and voluntarily disclose that you are late, IRAS says it will generally waive the late notification fine and penalties, though the GST on past sales is still payable, possibly in instalments. If you think you have already crossed S$1 million, act now rather than waiting for the year end.

Do it yourself or get help?

Checking the threshold and applying through myTax Portal is something an owner or bookkeeper can do. Getting the store, invoices and accounting software right from the effective date is where mistakes cost money, especially with several sales channels and payment providers.

Our Xero / QuickBooks Integration package (S$390) connects your store and payment providers to your accounting software with GST codes set correctly. For the tax position itself, speak to an accountant or tax adviser.