ERP

GST F5 and F8 Filing in Singapore (2026): What ERP Software Actually Does For You

Sherman Hsieh

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Last researched: 2 September 2026. Filing rules, due dates and penalty amounts are taken from IRAS’s own pages and were checked on that date. Statements about what individual ERP products do come from vendor and partner documentation and are labelled as such.

Every GST-registered business in Singapore files a GST F5 return, usually quarterly, and a GST F8 once it de-registers. The form is short — fifteen boxes — but every figure in it has to reconcile to the ledgers and the invoices behind it, and IRAS holds the business to that standard regardless of which system produced the numbers. That reconciliation is where the ERP does most of the work, which is why GST handling belongs on the shortlist criteria for a Singapore company choosing one, not a detail to check after the decision is made.

Before you buy, know exactly which parts of this job the software owns, which depend entirely on how it is configured, and which stay a finance-team decision no matter what system is in place. A good ERP classifies transactions by tax code as they are posted, builds the draft F5 from those codes, produces the IRAS Audit File on request, and, if it sits on the right tier of IRAS’s software register, files the return to myTax Portal directly through an API. What it cannot do is decide whether an export qualifies for zero-rating, whether a supplier’s invoice is valid for an input tax claim, or whether an expense is blocked. Those calls are made once, in the tax code configuration and the posting rules, and the system applies them thousands of times over. Get the configuration right and filing becomes a review exercise. Get it wrong and the system produces a wrong return with great efficiency — IRAS can penalise incorrect returns at up to 200% of the tax undercharged.

This guide is part of our Singapore ERP series. It covers what the F5 and F8 contain, when they are due and what late filing costs, what an ERP actually does for each obligation, how IRAS’s Accounting Software Register Plus and direct-filing API fit in, and where the systems in our Singapore ERP buyer’s guide stand on all of it.

What is in the GST F5

The F5 is filed through myTax Portal by a person authorised under Corppass for the “GST (Filing and Applications)” e-service. Corppass has two roles, Preparer and Approver; a Preparer can complete and save a draft but cannot submit, and anyone given access to all e-services becomes an Approver by default (IRAS, checked 2 September 2026). All figures are reported in Singapore dollars, and a nil return must still be filed for a period with no transactions.

IRAS describes the return as having fifteen boxes that must be completed, followed by scheme-specific boxes for the Import GST Deferment Scheme. The table below lists the boxes and, in the third column, where a properly configured ERP gets the number from (IRAS, Completing GST returns, checked 2 September 2026).

Two of these boxes cause more trouble than the rest. Box 13, revenue, is taken from the profit and loss account rather than from the tax codes, so it will not equal box 4 for most businesses, and IRAS says explicitly that an error in box 13 alone does not require a correction return (IRAS, Correcting errors, checked 2 September 2026). Box 7 depends entirely on the ERP knowing which purchases are blocked. IRAS lists motor car expenses, medical expenses and insurance, and private expenses as non-claimable, and it lists claiming input tax without a valid tax invoice as the most common error it finds (IRAS). An ERP that maps those expense accounts to a blocked tax code by default removes most of that risk; one that leaves it to whoever posts the invoice does not.

When the return is due, and what lateness costs

Most businesses file quarterly, on periods aligned to their financial year-end. A company with a December year-end files for January to March, April to June, July to September and October to December. Monthly filing is available on request, which businesses in a regular refund position often prefer, and special accounting periods can be approved for companies whose periods do not start and end on calendar months. Changing the financial year-end does not change the GST periods automatically; that needs a written request to IRAS through myTax Mail (IRAS, Changing GST accounting periods, checked 2 September 2026).

Both the return and the payment are due one month after the end of the period. Businesses on GIRO have their deduction taken on the 15th of the month after the due date, which is a month and a half of extra float that is worth setting up on day one (IRAS, Due dates, checked 2 September 2026).

Source: IRAS, Due dates and requests for extension, checked 2 September 2026. Businesses on other quarterly cycles or monthly filing follow the same one-month rule from the end of their own period.

IRAS’s position on extensions is that one month is a reasonable deadline and none will be granted as a matter of course. The exceptions are a newly registered business’s first return, which can get one month, and a short list of documented reasons that each get two weeks: a computer system breakdown, the purchase of new accounting software, key accounting staff on long medical leave, a company restructuring, and errors in submitting through seamless filing software via API. Requests must be lodged at least five working days before the due date. The list of reasons IRAS will not accept is instructive for anyone planning an ERP project: staff resignation without handover, year-end closing, new accounts staff who do not know GST, and not enough manpower are all explicitly refused (IRAS, checked 2 September 2026). A go-live scheduled for the last week of a GST quarter is therefore a risk the business carries alone.

The penalties are fixed and automatic. A late submission penalty of S$200 is imposed the moment a return misses its due date, with a further S$200 for every completed month it stays outstanding, up to S$10,000 per return. IRAS may also issue an estimated assessment and add a 5% late payment penalty to the estimated tax, and repeated non-filing leads to a court summons with a fine of up to S$5,000 per offence (IRAS, Late filing, checked 2 September 2026). On the payment side, a 5% penalty applies to tax unpaid at the due date, and if it is still unpaid 60 days later a further 2% is added for each month, up to 50% of the tax. IRAS can appoint the business’s bank as a collection agent, which in practice freezes the account until the debt is cleared (IRAS, Late payment, checked 2 September 2026).

Errors in a filed return are corrected with a GST F7. Small errors, where the net GST in error across all affected periods is S$3,000 or less and other boxes are out by no more than 5% of box 4, can be adjusted in the next F5 instead. Errors must be corrected within five years of the end of the period, and if they are corrected more than a year after the F5 deadline, penalties can apply; corrected within a year, IRAS says no penalty is imposed (IRAS, checked 2 September 2026). This is the practical reason to run a GST reconciliation every quarter rather than at year-end: a mistake found in the following quarter is free to fix, and one found at audit two years later is not.

The GST F8 final return

A business must apply to cancel its GST registration within 30 days of ceasing to make taxable supplies, ceasing business, transferring the business as a whole, or changing its legal form. Voluntary registrants must stay registered for at least two years before they can cancel. Once cancellation is approved, IRAS issues a GST F8 covering the period up to the last day of registration, and it is due one month after the end of that period along with any outstanding returns and payments (IRAS, Cancelling GST registration, checked 2 September 2026).

The F8 has the same boxes as an F5 and two additional requirements. The business must account for output tax on business assets held on the last day of registration, at their open market value, if that value exceeds S$10,000 and input tax was claimed on them when they were bought. Assets include non-residential property, fixed assets such as equipment and vehicles, and unsold inventory. It must also account for output tax on supplies delivered before cancellation but invoiced or paid afterwards. IRAS’s own example has equipment bought for S$100,000 and property bought for S$800,000, valued at S$1,120,000 on the last day, producing S$100,800 of output tax at 9%, reported in box 1 and box 6 of the F8 (IRAS, checked 2 September 2026).

For the ERP, the F8 is a test of records rather than of the tax engine. Producing it requires a fixed asset register that records whether input tax was claimed on each asset, a closing stock valuation, and a report of goods delivered but not yet invoiced at the cut-off date. Companies that de-register after a restructuring, a change from sole proprietorship to a private limited company, or a group reorganisation are usually also migrating systems at the same time, and the F8 is easier to prepare from the old system before the migration than from the new one afterwards. Records must in any case be kept for five years from the date of each transaction, even after registration is cancelled.

What the ERP actually does

GST compliance breaks into four functions. Evaluate an ERP against each one separately — not on whether it broadly “does GST”.

Classification at the point of posting. Every sales and purchase line carries a tax code, and the tax code determines which box it lands in. The standard Singapore set covers standard-rated, zero-rated and exempt supplies, standard-rated and zero-rated purchases, imports, blocked input tax, out-of-scope, reverse charge and the various import schemes. A well-localised ERP ships with these codes, maps them to the F5 boxes, and lets the administrator set defaults by customer, supplier, item and general ledger account so that a purchase of motor vehicle insurance is blocked automatically and an export to a Malaysian customer is zero-rated automatically. This is the single most valuable thing the system does, and it is entirely dependent on the configuration done at implementation. IRAS recognises it as a recommended feature in its own words: mapping general ledger accounts to the disallowed expenses tax code so that such transactions are tagged as blocked by default (IRAS, Recommended features for ASR+, checked 2 September 2026).

Generation of the draft return. The system sums the coded lines for the period into the F5 boxes, applies the exchange rates for foreign currency transactions, and produces a draft with the supporting listing behind each box. IRAS calls this auto-generation of a draft GST return and lists it as a recommended feature. The draft still needs a human reconciliation to the general ledger, because the GST control accounts and the tax code totals drift apart whenever someone posts a manual journal to a GST account or a credit note is coded differently from the invoice it reverses. Xero, for instance, states that its F5 is auto-populated and includes foreign currency gains and losses, and that users should review and finalise the return with their adviser before submitting (Xero Singapore, vendor, checked 2 September 2026).

The IRAS Audit File. IRAS can ask any GST-registered business to produce the IAF, a structured listing of sales and purchases in a prescribed pipe-delimited text format, to support the figures in its returns. Most localised ERPs generate it: NetSuite’s Singapore Localization SuiteApp produces it in text format, Microsoft’s Dynamics 365 Finance added the text-format IAF in version 10.0.26, and Business Central partners such as CyanSYS include IAF generation in their Singapore add-ons (Oracle NetSuite documentation, Microsoft Learn, CyanSYS, all vendor or partner documentation, checked 2 September 2026). Ask to see the IAF produced from a demo dataset; a system that cannot produce it on demand will cost you consulting hours in the middle of an audit.

Direct submission through the IRAS API. IRAS publishes APIs that let accounting software file the F5 and F8, and file an F7 correction, directly from the software to myTax Portal without re-keying the figures. The user still authenticates with Singpass under the business’s Corppass authorisation, so the Preparer and Approver controls are preserved. IRAS lists software that has passed its integration testing for this on the Accounting Software Register Plus, covered in the next section. Direct filing removes transcription errors and gives the software an acknowledgement number to store against the period, but it does not change what is filed; the review step before submission is the same.

Alongside those four functions, the InvoiceNow requirement adds a fifth data flow: transmission of invoice data for supplies and purchases to IRAS through the Peppol network, due by the earlier of the date the GST return is filed or its due date. IRAS’s page on the requirement states that businesses remain responsible for their existing obligations, including filing accurate GST returns and keeping records for five years, after they begin transmitting invoice data (IRAS, GST InvoiceNow Requirement, checked 2 September 2026). New voluntary registrants have been in scope since 1 April 2026, and existing businesses phase in between 1 April 2028 and 1 April 2031 based on box 4 of their 2025 returns. IRAS notified businesses registered before 2026 of their individual implementation dates from mid-2026. Our InvoiceNow and Peppol guide goes through the phases and what to check in an ERP.

The IRAS ASR+ register, and what the tiers mean

The Accounting Software Register Plus is IRAS’s list of software whose tax integrations it has tested. A product qualifies for Tier 1, 2 or 3 depending on how many of three digital products it incorporates: submission of Corporate Income Tax Form C-S, submission of GST F5 and F8 returns, and accreditation as an InvoiceNow-Ready Solution Provider by IMDA. Other recommended features, including F7 submission, auto-generation of the draft return, blocked input tax automation and filing reminders, are noted against each listing. IRAS says it has only performed integration testing of the listed software and makes no warranty about anything else (IRAS, ASR+, checked 2 September 2026).

Two things about the register matter for a buyer in late 2026. First, the tier tells you which capabilities the product has, not how good it is; a Tier 1 listing for InvoiceNow alone says nothing about whether the software can file the F5 by API. Second, every listing we read on 2 September 2026 carried a listing period ending 30 June 2026, and IRAS states on its recommended-features page that it is rebranding the ASR+ framework into a new partnership programme and has put new applications on hold during the transition (IRAS, checked 2 September 2026). The register is still the best evidence available of which products file directly, but ask the vendor whether its listing is being carried into the new programme.

Sources: IRAS ASR+ listing (primary), read 2 September 2026; Xero blog (vendor); Oracle NetSuite documentation (vendor); CyanSYS (Microsoft partner). Listings are by product, version and provider, and the register changes; confirm the exact line item for the edition and partner you are buying.

The pattern across the table is clear: the small-business and mid-market products built or localised in Singapore file directly, while the global mid-market ERPs sold through partners generally do not — their partners have prioritised InvoiceNow accreditation instead. That is the right call, since InvoiceNow is mandatory on a fixed timetable and API filing is optional. For a finance team it means the quarterly F5 for SAP Business One or a Tier 1 Business Central deployment is a report printed from the ERP and keyed into myTax Portal by the Approver, which takes perhaps twenty minutes a quarter and is not a reason to reject a product that fits the business better in every other way. Our NetSuite vs Business Central comparison and NetSuite in Singapore guide cover the two systems where this question comes up most.

The configuration decisions that determine the return

The return is a summary of tax codes. That makes the tax-code decisions made at implementation the GST project, not a line item within it — and five of them deserve a named owner on the finance side rather than being left to the implementation consultant.

Default codes by account and by counterparty. Blocked expense accounts, overseas customers, overseas suppliers and import-related accounts should default to the correct code so that the person posting the document does not have to know the rules. The test is whether a new accounts assistant can post a motor insurance invoice and have it land in the blocked code without being told.

Zero-rating evidence. IRAS will not accept zero-rating on the basis that the customer is overseas; goods must be exported with documentation and services must meet the international services rules. The ERP cannot judge this, but it can require an export permit reference or a delivery address outside Singapore before the zero-rated code is allowed on a sales line. Ask whether that kind of validation is configurable.

Foreign currency. Figures must be reported in Singapore dollars using an acceptable exchange rate at the time of supply, and the rate used for the GST amount on the invoice should match the rate used in the return. Systems that store the SGD GST amount on the invoice at the time of posting avoid the rounding differences that IRAS’s F7 FAQ spends several questions on; ask the vendor to show where that amount is held.

Time of supply. Output tax is accounted for at the earlier of invoice and payment, and input tax is claimed in the period the supplier’s invoice is dated or, if the business has adopted that basis, the period it is posted. The ERP’s tax point setting should reflect the basis the business has chosen and applied consistently, because switching between the two shifts GST between quarters.

Reverse charge and imported services. Businesses that are partially exempt, or that belong to a GST group with exempt members, must account for reverse charge on imported services in box 14. Fully taxable businesses generally do not. The ERP needs the reverse charge code available and switched off by default for a fully taxable company, so that it is not applied by accident.

Migrating systems without losing five years of records

IRAS’s record-keeping FAQ answers a question every ERP buyer has: whether historical transactions have to be migrated into the new system. They do not. The business must, however, retain the transactions recorded in the old software for at least five years from the end of the relevant GST period and be able to retrieve them if IRAS asks, together with the source documents, schedules and bank statements behind them (IRAS, Keeping records, checked 2 September 2026). Losing the supporting documents has a direct cost: input tax claims without a valid invoice are disallowed, and exports without evidence are treated as local supplies at 9%.

The practical consequence is a decommissioning plan for the old system. A read-only licence, a database backup that someone can actually restore, or a full export of the ledgers, tax listings and IAF for every open period all satisfy the requirement; a cancelled subscription with no export does not. Build this into the ERP contract, and check whether the outgoing vendor charges for access after termination.

Three Singapore buyer scenarios

A S$4 million services firm on Xero, considering an upgrade. Xero already generates and files the F5 directly and sits at Tier 2 on the register — GST filing is not a reason to move. The real reasons, if there are any, are inventory, projects or multi-entity consolidation. Move to Odoo or a Tier 1 Business Central package instead, and expect to key the F5 into myTax Portal from a report rather than filing from the system — and make the partner demonstrate the IAF export before signing anything.

A S$30 million distributor with a Major Exporter Scheme licence, replacing an old on-premises ERP. Box 9 and the import scheme codes are the differentiator. The shortlist, SAP Business One, Business Central or NetSuite, must show scheme-specific import codes, a tax listing that separates MES imports from ordinary purchases, and an IAF that carries the permit numbers. Direct filing is a convenience; a correct box 9 and a clean IAF are what an IRAS scheme review will test. Time the go-live for the first month of a GST quarter, because IRAS does not accept new-system problems as grounds for an extension beyond the two weeks it allows for a documented software purchase.

A group restructuring three Singapore entities into one, with two GST registrations to cancel. Each cancelled entity needs an F8, an output tax calculation on assets held at the open market value if it exceeds S$10,000, and a cut-off report of goods delivered but not invoiced. Prepare the F8s from the outgoing systems before migrating, keep those systems retrievable for five years, and confirm whether the transfer qualifies as a going concern, which removes the deemed supply on assets. The new entity’s ERP should be configured and tested for GST before it goes live, because it will inherit the filing frequency and the InvoiceNow phase of the surviving registration.

Questions to ask any vendor or partner

Which line on the IRAS ASR+ register is this product, and which tier? Get the product name, version and provider as listed, and ask whether the listing is being carried into IRAS’s replacement programme.

Show me the F5 from a demo dataset, with the listing behind each box. Then post a blocked expense, an export and a foreign currency invoice and watch where they land.

Show me the IAF. It should be produced from a menu, not by a consultant.

How is an F7 handled? Whether the system files it by API or not, it should be able to reproduce the original return and the corrected figures for each affected period.

Who owns the tax code configuration after go-live, and what happens when IRAS changes a rule? The 2023 and 2024 rate changes required new codes and transitional handling, and the InvoiceNow phases will require more. Ask how the last change was delivered and how long it took.

Frequently asked questions

How often do I file the GST F5?

Quarterly by default, on periods aligned to your financial year-end. Monthly filing can be requested, and IRAS can approve special accounting periods for non-calendar fiscal calendars. Return and payment are due one month after the period ends.

What is the penalty for filing late?

S$200 immediately, plus S$200 for each completed month the return stays outstanding, up to S$10,000 per return. Late payment carries a separate 5% penalty, rising by 2% a month after 60 days to a maximum of 50% of the tax.

Does my ERP file the return for me?

If it is listed on Tier 2 or Tier 3 of the IRAS ASR+ register, or the vendor has enabled IRAS’s API in the product, it can submit the F5 and F8 directly after a Singpass login. Otherwise it produces the figures for entry into myTax Portal. In both cases the finance team reviews the draft before submission.

What is the difference between the F5, F7 and F8?

The F5 is the regular return. The F7 corrects errors in a return already filed. The F8 is the final return issued when GST registration is cancelled, and it additionally accounts for output tax on assets held at de-registration.

Does InvoiceNow replace the GST return?

No. IRAS states that businesses in scope of the GST InvoiceNow Requirement remain responsible for filing accurate GST returns and keeping records. Invoice data is transmitted by the earlier of the return’s filing date or due date, and the return is still filed.

What is the IRAS Audit File?

A structured text listing of sales and purchases that IRAS can request to verify the figures in your returns. Most Singapore-localised ERPs generate it; check that yours does before you need it.

Sources

• IRAS, Completing GST returns (GST F5 and F8), checked 2 September 2026. Primary source.
• IRAS, Due dates and requests for extension, checked 2 September 2026. Primary source.
• IRAS, Late filing or non-filing of GST returns (F5/F8), checked 2 September 2026. Primary source.
• IRAS, Late payment or non-payment of GST, checked 2 September 2026. Primary source.
• IRAS, Correcting errors made in GST return (filing GST F7), checked 2 September 2026. Primary source.
• IRAS, Cancelling GST registration and filing the GST F8, checked 2 September 2026. Primary source.
• IRAS, Changing GST accounting periods, checked 2 September 2026. Primary source.
• IRAS, Overview of GST e-filing process, checked 2 September 2026. Primary source.
• IRAS, Keeping records, checked 2 September 2026. Primary source.
• IRAS, GST InvoiceNow Requirement, checked 2 September 2026. Primary source.
• IRAS, Overview of GST rate change, checked 2 September 2026. Primary source.
• IRAS, Accounting Software Register Plus (ASR+) and ASR+ listing, read 2 September 2026. Primary source.
• IRAS, Recommended digital products and features for ASR+, checked 2 September 2026. Primary source.
• Xero Singapore, GST software: prepare GST F5 returns online, checked 2 September 2026. Vendor.
• Xero, Direct filing of the Singapore GST F5 return is coming to Xero, October 2022, updated November 2023. Vendor.
• Oracle NetSuite, Submitting Singapore GST F5 and F8 returns and Singapore Localization, checked 2 September 2026. Vendor documentation.
• Microsoft Learn, IRAS Audit File (IAF) for Singapore in Dynamics 365 Finance, checked 2 September 2026. Vendor documentation.
• CyanSYS, Singapore localization for GST and Peppol on Microsoft AppSource, April 2024. Microsoft partner.
• AFON, SAP Business One Singapore, checked 2 September 2026. SAP and Microsoft partner.
• Singapore Secretary Services, GST return filing workflow and checklist 2026, checked 2 September 2026. Corporate services firm.

1752 Overall Score

Sherman Hsieh

CEO & Editor-in-Chief, Business-Software.com
Independent analysis of enterprise software — ERP, CRM and more

Sherman Hsieh is the founder, CEO, and editor-in-chief of Business-Software.com. He leads the site's independent, buyer-focused coverage of ERP, CRM, and other business systems, including vendor-neutral comparisons, pricing analysis, and implementation guidance. Before founding Business-Software.com, Sherman was an executive at Siebel ...