What is the GST F5?
The GST F5 is the quarterly GST return that every GST-registered Singapore business must file with IRAS. It reports the business's standard-rated sales, zero-rated sales, exempt sales, purchases, output tax, input tax, and the net GST payable to (or refundable by) IRAS for the accounting period.
When the GST F5 is due
The standard GST accounting period is 3 months (quarterly). Both the F5 and the payment are due one month after the end of the accounting period.
For example, for the accounting period 1 July – 30 September, the F5 and any GST owed are due by 31 October.
Important: you must file the F5 even if there was no business activity in the period — a "nil return". Late filing or non-filing incurs penalties.
Where you file
GST returns are e-filed through myTax Portal. Paper filing is not accepted. Filing requires a Corppass-linked authorisation.
What the F5 contains
The return walks through standard boxes including:
- Total value of standard-rated supplies (Box 1) and the output tax on them (Box 6)
- Total value of zero-rated supplies (Box 2) and exempt supplies (Box 3)
- Total value of taxable purchases (Box 5) and the input tax claimed (Box 7)
- Net GST to pay or claim (Box 8 = Box 6 − Box 7)
- Adjustments, bad-debt relief, and import-related boxes where applicable
If you've adopted the GST InvoiceNow Requirement, much of this data is already with IRAS — but you still file the F5.
Extensions
The one-month deadline is considered reasonable, so extensions are not routinely granted. If you have a genuine reason (e.g. system migration, key staff illness), submit the extension request via myTax Portal at least 5 working days before the filing due date with supporting documents.
Other GST return forms (briefly)
- GST F7 — to correct errors in a previously filed F5.
- GST F8 — final return when you de-register from GST.
This page focuses on the F5; the F7 will have its own glossary entry in a future batch.
Related terms
- GST (Goods and Services Tax) — GST is Singapore's broad-based consumption tax — currently 9% — charged on most goods, services and imports.
- GST registration threshold — Singapore businesses must register for GST when taxable turnover exceeds S$1 million — either retrospectively or on a forecast (prospective) basis.
- Input tax vs output tax — Output tax is the GST you charge customers on sales.
- GST InvoiceNow Requirement — The GST InvoiceNow Requirement is IRAS's mandate that GST-registered businesses transmit invoice data to IRAS via the InvoiceNow Peppol network.
Sources
Last reviewed 29 May 2026. Verify any thresholds or dates against the official source above before relying on them.