The GST F5 form (Form 5) is your periodic GST return, and it's due one calendar month after your accounting period ends. For a quarter ending 31 March, that's 30 April. Every GST-registered business must file — even a quarter with no transactions needs a NIL return with zeros in every box. Miss it and IRAS charges an immediate $200, then another $200 for each month it stays outstanding, up to $10,000 per return.
GST is a 9% consumption tax. The F5 reconciles the GST you collected (output tax) against the GST you paid (input tax); the difference is what you pay IRAS or get refunded.
The essentials
| What | GST F5 — periodic GST return |
| Cycle | Quarterly by default (monthly or half-yearly on IRAS approval) |
| Deadline | One month after accounting period ends — return AND payment |
| How | e-File via IRAS myTax Portal (Corppass, "GST (Filing and Applications)" Approver role) |
| Currency | All figures in SGD |
| Late filing | S$200, plus S$200 for each completed month outstanding, up to S$10,000 per return |
| Late payment | 5% of the unpaid tax; then 2% a month if still unpaid 60 days later, up to 50% |
GST filing periods and their due dates: Jan–Mar → 30 Apr · Apr–Jun → 31 Jul · Jul–Sep → 31 Oct · Oct–Dec → 31 Jan.
The eight boxes
Total standard-rated supplies (9% sales, excluding GST)
Zero-rated supplies (exports, international services)
Exempt supplies (financial services, residential property)
Total supplies (1+2+3)
Total taxable purchases (excluding GST)
Output tax due: the GST you charged on standard-rated supplies
Input tax claimed
Net GST: Box 6 − Box 7. Positive = pay IRAS; negative = refund.
The return has fifteen boxes in all; these eight carry the GST. The portal adds up Box 4 and works out Box 8. Check both against your own GST summary before you submit.
How to file, step by step
- 1Reconcile first. Match invoices, permits, credit/debit notes against ledger. Confirm GST codes before starting.
- 2Log in to mytax.iras.gov.sg with Corppass. Need GST (Filing and Applications) Approver role.
- 3Open the return: GST → File GST Return (F5/F7/F8) → select period.
- 4Enter consolidated figures. Apply 9% to standard-rated, 0% to zero-rated, account for reverse charge.
- 5Check Box 6 and Box 8 against internal GST summary. Reconcile variances.
- 6Review declaration and submit. Keep acknowledgement.
- 7Pay by deadline. The payment is due on the same date as the return.
Two things that trip people up
NIL quarter still files
Zeros in every box, or you're penalised.
Corrections use GST F7
You cannot edit a submitted F5. File a GST F7 (amendment). Final return = GST F8.
The InvoiceNow change
From 1 April 2026, businesses that register for GST voluntarily must submit invoice data to IRAS through an InvoiceNow-Ready Solution. F5 deadlines are unchanged. See our InvoiceNow deadline guide.
Where MassAdmin fits
MassAdmin keeps double-entry books with a Singapore chart of accounts, with invoices, bills, credit notes and reports, in the same login as payroll. It does not prepare your GST F5 in the current release.
You prepare your GST F5 and file it on myTax Portal.
30-day free trial · no card
Sources
- Source: IRAS, Late Filing or Non-Filing of GST Returns (F5/F8) (updated 10 August 2026). Checked 10 October 2026.
- Source: IRAS, Late payment or non-payment of GST (updated 10 August 2026). Checked 10 October 2026.
This guide is for general information only and does not constitute legal or financial advice.
Related
- GST InvoiceNow deadlines
- IR8A and AIS
- InvoiceNow-Ready Solutions
- Singapore SME compliance calendar 2026 — every payroll & tax deadline in one place
Questions
When is GST F5 due?
One month after accounting period ends — both return and payment.
What are the penalties for late GST filing?
Late filing: S$200 straight away, then S$200 for each completed month the return stays outstanding, up to S$10,000 per return. Late payment: 5% of the unpaid tax; if it is still unpaid 60 days later, a further 2% a month, up to 50%.
Do I file if I had no sales?
Yes. NIL return with zeros required.
What’s the difference between F5, F7 and F8?
F5 = normal return. F7 = correction. F8 = final return on deregistration.
How do I correct a mistake after submitting?
Can’t edit submitted F5. File GST F7.
What is Box 8?
Net GST: Box 6 minus Box 7. Positive = pay IRAS; negative = refund.
Where do I get the GST F5 form?
There is no separate paper form to download. The GST F5 is filed electronically via the IRAS myTax Portal — log in with Corppass, navigate to GST → File GST Return, and complete it online.