Every Goods and Services Tax (GST) registered business in Singapore must file a return each accounting period, even with zero activity. Miss the deadline and the Inland Revenue Authority of Singapore (IRAS) charges an automatic penalty. The current GST rate is 9%, effective 1 January 2024.
Your GST return and payment are both due one calendar month after your accounting period ends, according to IRAS’s GST filing due dates/filing-gst/due-dates-and-requests-for-extension). This guide covers the rate, Form GST F5 boxes, the myTax Portal steps, deadlines, penalties, and refunds.
What Is GST Filing in Singapore?
GST filing is the periodic return that reconciles the GST you collected against the GST you paid. Goods and Services Tax is a 9% consumption tax on supplies made in Singapore and on imported goods. Net GST equals output tax minus input tax. A positive figure is paid to IRAS; a negative figure is refunded.
Every GST-registered business has three obligations. You charge and collect output tax on taxable supplies. You claim input tax on eligible business purchases. You file the return and pay any net GST by the deadline.
The 9% rate is recent, so older invoices and content still show 7% or 8%. The progression matters when supplies span a rate-change date. See IRAS’s overview of the GST rate change/gst-rate-change/gst-rate-change-for-business/overview-of-gst-rate-change) for transitional rules.
| GST rate | Effective from | Source |
|---|---|---|
| 3% | 1 Apr 1994 | MOF |
| 4% | 2003 | data.gov.sg / IRAS |
| 5% | 2004 | data.gov.sg / IRAS |
| 7% | 2007 | data.gov.sg / IRAS |
| 8% | 1 Jan 2023 | IRAS |
| 9% | 1 Jan 2024 | IRAS |
Who Must File GST Returns in Singapore?
Any GST-registered business must file a return every accounting period, including a nil return when there was no activity. Registration is compulsory once taxable turnover exceeds S$1 million, under either a retrospective 12-month test or a prospective one, per IRAS. Businesses below the threshold can register voluntarily, subject to a minimum two-year commitment.
Filing is mandatory once you register, whether compulsorily or voluntarily. A nil GST return is still required for a period with no taxable supplies, and skipping it still incurs a penalty. Under IRAS’s guidance on when you must register for GST/gst-registration-deregistration/do-i-need-to-register-for-gst), you apply within 30 days of crossing either test.
Foreign companies must be registered before they can file, and some need a local agent. See Commenda’s guide to GST registration for foreign companies for the prerequisites.
When Is the GST Return Due Date?
Your GST return and payment are both due one calendar month after your accounting period ends, per IRAS. Quarterly is the default cycle IRAS assigns at registration, though monthly and half-yearly filing are available on approval. A January to March quarter is due 30 April; April to June is due 31 July.
| Accounting period | Filing and payment deadline | Source |
|---|---|---|
| Jan – Mar | 30 April | IRAS |
| Apr – Jun | 31 July | IRAS |
| Jul – Sep | 31 October | IRAS |
| Oct – Dec | 31 January | IRAS |
Payment timing depends on your method. For non-GIRO payers, the filing and payment deadlines are the same date. For GIRO payers, the return is still due by the deadline, but the GIRO deduction happens on the 15th of the month after the due date, which eases cash-flow planning. Accepted methods are GIRO, PayNow QR, internet banking, and telegraphic transfer.
What Do You Report on Form GST F5?
Form GST F5 reports your supplies, purchases, output tax, input tax, and net GST across numbered boxes. Box 1 captures standard-rated supplies, Box 6 the output tax due, Box 7 the input tax claimed, and Box 8 the net GST payable or refundable. All GST-registered businesses file the F5 electronically.
| Box | What you report | Source |
|---|---|---|
| Box 1 | Total value of standard-rated supplies (excludes GST) | IRAS |
| Box 2 | Total value of zero-rated supplies (exports, international services) | IRAS |
| Box 3 | Total value of exempt supplies | IRAS |
| Box 4 | Total value of Boxes 1 to 3 | IRAS |
| Box 5 | Total value of taxable purchases (excludes GST) | IRAS |
| Box 6 | Output tax due | IRAS |
| Box 7 | Input tax and refunds claimed | IRAS |
| Box 8 | Net GST payable or refundable (Box 6 minus Box 7) | IRAS |
| Boxes 9–15 | Additional declarations: imports under approved schemes, reverse charge, and Overseas Vendor Registration items | IRAS |
Zero-rated supplies are taxed at 0% and still let you claim input tax. Exempt supplies carry no GST and generally no input tax claim. Two related forms handle changes: file Form GST F7 to correct errors in a previously submitted F5, and file Form GST F8 as your final return when you cancel GST registration.
How to File a GST Return on myTax Portal (Step-by-Step)
All GST filing is electronic through the IRAS myTax Portal, accessed with Corppass. Seven steps take you from reconciled records to a submitted, paid F5.
Step 1: How do you prepare and reconcile records?
Gather and reconcile your sales invoices, purchase and tax invoices, import permits, credit and debit notes, and ledger balances. Your accounting software GST codes must be correct before you start.
Step 2: How do you calculate output tax?
Apply 9% to standard-rated supplies, 0% to zero-rated supplies, and account for reverse charge where it applies. Adjust for credit notes and bad debt relief.
Step 3: How do you calculate input tax?
Total the claimable GST on eligible business purchases, including import GST. Exclude blocked items such as entertainment, private motor cars, and staff medical benefits.
Step 4: How do you determine your net GST position?
Net GST is Box 6 output tax minus Box 7 input tax. A positive figure is payable; a negative figure is refundable.
Step 5: How do you log in with Corppass?
Log in to the myTax Portal with Corppass, then select GST and File GST F5. The individual must hold the GST e-Filing role.
Step 6: How do you complete and review the F5 boxes?
Enter your figures box by box. The portal auto-computes Box 8. Review every box against your ledger before you confirm.
Step 7: How do you submit and pay by the deadline?
Submit the return and save the acknowledgment page and reference number. Pay by GIRO, PayNow QR, internet banking, or telegraphic transfer. Remember GIRO deducts on the 15th of the following month.
What Are the Penalties for Late GST Filing?
IRAS imposes an immediate S$200 late submission penalty the moment your GST return is overdue. A further S$200 is added for each completed month it stays unfiled, capped at S$10,000 per return. If you do not file, IRAS can raise an estimated assessment, and non-filing can lead to a court fine on conviction.
| Penalty | Amount | Source |
|---|---|---|
| Late submission penalty | S$200 immediately once the return is overdue | IRAS |
| Continued non-filing | Additional S$200 for each completed month outstanding | IRAS |
| Maximum per return | Capped at S$10,000 per outstanding return | IRAS |
| Estimated Notice of Assessment (NOA) | IRAS estimates your GST and demands payment | IRAS |
| Court conviction for non-filing | Fine up to S$5,000 per offence | IRAS |
A separate late payment penalty also applies to tax unpaid by the due date. See IRAS’s late filing and non-filing penalties/filing-gst/late-filing-or-non-filing-of-GST-returns-f5-f8) for the current figures and enforcement steps.
How Do You Claim a GST Refund in Singapore?
When your input tax (Box 7) exceeds your output tax (Box 6), the F5 itself is your refund claim. IRAS refunds the net amount within the statutory window: three months for quarterly filers and one month for monthly filers. In practice, IRAS reports more than 98% of GST refunds are processed within 30 days.
| Refund measure | Figure | Source |
|---|---|---|
| Statutory window, quarterly filers | Within 3 months of return receipt | IRAS |
| Statutory window, monthly filers | Within 1 month of return receipt | IRAS |
| Refunds processed within 30 days | More than 98% | IRAS |
| Refunds paid within 7 days | Over 95% | IRAS |
Refunds slow down when documentation is incomplete, figures contain errors, or other returns are outstanding, and IRAS may run a pre-refund review. Clean records speed the cycle. See IRAS’s GST payments and refunds guidance/gst-payments-refunds) for the statutory timelines.
What Is Reverse Charge GST in Singapore?
Reverse charge makes certain GST-registered businesses account for GST on imported services and low-value goods (LVG) as if they were the supplier. It applies to businesses that cannot claim full input tax, such as partially exempt financial and property firms. They report the GST in the relevant F5 boxes and claim input tax under the normal rules.
Reverse charge is distinct from the Overseas Vendor Registration (OVR) regime, which requires overseas suppliers to register and charge GST. IRAS extended OVR to non-digital services and low-value goods with effect from 1 January 2023.
What Are Common GST Filing Mistakes and Audit Triggers?
The most common GST filing mistakes are claiming non-allowable input tax, misclassifying zero-rated supplies, skipping nil returns, and figures that do not reconcile to your accounts. Repeated errors, frequent F7 corrections, and GST turnover that does not match your income tax return are known audit triggers, because IRAS cross-checks GST F5 data against your corporate tax filings.
Using 8% instead of 9% on invoices that span the rate change is a frequent error. So is claiming import GST without a permit in the correct name. Keeping bookkeeping aligned to your chart of accounts keeps Box 4 reconciled to your records.
How long must you keep GST records?
GST-registered businesses must keep records for at least five years, per IRAS. That covers tax invoices, import and export documents, accounting ledgers, and payment records. Failure to keep them can lead to disallowed input tax claims and penalties. See IRAS’s record-keeping requirements/basics-of-gst/invoicing-price-display-and-record-keeping/keeping-records).
How Does GST Filing Differ From Corporate Tax Filing in Singapore?
GST filing and corporate tax filing are separate obligations with separate forms and deadlines. You file GST on Form GST F5, usually quarterly, one month after each period ends. You file corporate income tax on Form C or Form C-S once a year, by 30 November for e-filing with IRAS. The two figures must reconcile.
| Feature | GST filing | Corporate tax filing |
|---|---|---|
| Frequency | Quarterly by default | Annual |
| Basis | Transaction-based | Profit-based |
| Form | Form GST F5 | Form C / Form C-S |
| Deadline | One month after period end | 30 November each year (e-filing) |
Missing GST deadlines can trigger faster enforcement than corporate tax delays. For the current rates and reliefs, see Commenda’s guide to Singapore corporate tax rates.
GST Filing Checklist
Run this checklist before you submit each GST F5:
- Registration status and filing frequency confirmed
- Corppass access with the GST e-Filing role active
- Sales invoices captured with GST at 9%
- Purchase tax invoices on hand and valid
- Import permits reconciled to import GST claimed
- Blocked input tax excluded
- Zero-rated and exempt supplies classified correctly
- Reverse charge on imported services accounted for, if applicable
- Box 4 total supplies reconciled to your ledger
- Net GST (Box 8) reviewed before submission
- Filed and paid before the deadline, acknowledgment saved
- Records retained for five years
How Commenda Helps With GST Filing in Singapore
Commenda’s global indirect tax software tracks your GST registration obligations, filing deadlines, and returns across every jurisdiction you operate in, so nothing slips past a due date. It connects to your books through 100+ ERP, API, and custom integrations, keeping GST-relevant data clean and reconciled for accurate F5 filing.
If you are expanding into Singapore, start with Commenda’s guides to GST registration for foreign companies and Singapore corporate tax rates, and use the compliance calendar to track filing deadlines by entity.
Book a demo to get your Singapore GST filing calendar and a compliance review.
