A GST-registered business in Singapore files Form F5 through IRAS myTax Portal, normally every quarter and normally one month after the period ends. The return reports output tax at 9 %, input tax you claim and the net amount you pay or recover. Late filing and payment are both penalised.
Form F5 is the standard GST return in Singapore. It asks for total standard-rated supplies, total zero-rated supplies, total exempt supplies, total taxable purchases, the output tax due, the input tax and refunds claimed, and the net GST payable or refundable. Each figure is entered in Singapore dollars.
The boxes separate supplies by their tax treatment, so a mixed business must classify every sale before filing. A sale to a customer in Singapore for a service performed in Singapore is usually standard-rated. A qualifying export is zero-rated. A sale of an exempt item, such as certain financial services, goes to the exempt box.
The net figure is output tax minus input tax. A positive result is payable to IRAS, and a negative result is a refund claim, which IRAS may review before paying. A refund claim with large unusual amounts is the most likely return to attract questions.
The return also asks about imports, goods bought under a GST-suspending scheme and other special items. Read the form instructions on the IRAS website each period, because boxes are added or reworded when the rules change.
Start from the sales ledger. List every invoice and credit note in the period, with its date, customer, amount before GST, GST amount and tax code. Totals by tax code feed the supply boxes, and the sum of the GST column is the output tax. Check that the invoice date, not the payment date, decides the period.
Then take the purchase ledger. Claim input tax only where you hold a valid tax invoice addressed to your business, the purchase serves taxable supplies, and the item is not on the blocked list. Entertainment, club subscriptions and private motor car expenses are common exceptions, so classify each line before summing.
Reconcile the totals to the general ledger before you open the portal. The GST control account should equal the net amount on the return. If the difference is small, find it, because small errors repeated every quarter add up to a review letter.
Adjustments follow their own rules. Credit notes reduce output tax in the period in which they are issued, and bad debt relief has conditions, including a time limit and written notice to the customer. Ask your accountant before claiming either.
An authorised user logs in through CorpPass with the right role, opens the GST section, selects the period and enters the figures. The portal checks arithmetic but does not check whether an invoice is correct, so the check is yours. Submit before the due date, which is normally the end of the month after the period closes.
IRAS gives a confirmation reference for each filing. Save the confirmation and the working papers together. If a figure is queried, a file that contains the return, the ledgers and the key invoices answers the question in one email.
Payment is made through channels listed by IRAS, such as GIRO or electronic transfer. GIRO arrangements collect the amount after the due date by a set number of days, so check the schedule. Late payment attracts a penalty on top of the tax, even when the return was filed on time.
The most frequent error is claiming input tax on an invoice that is addressed to the wrong entity, lacks the supplier's GST number, or is a pro forma rather than a tax invoice. IRAS can disallow the claim and ask for a penalty if the pattern is systematic.
Zero-rating without evidence is the second. Exports require proof, such as the shipping document and the export permit for goods, and international services must meet the conditions for the zero rate. If the file cannot show them, IRAS can treat the supply as standard-rated and assess the tax.
Another is reporting in the wrong period. An invoice issued in March for a service delivered in April is still a March tax point in most cases, and shifting it to smooth cash flow is not permitted.
A fourth is forgetting reverse charge on imported services where it applies, which is a separate computation. Check IRAS guidance if you buy services from overseas suppliers regularly.
When you find an error after filing, do not simply adjust the next return. For small errors IRAS allows correction within defined limits in the next return, while larger or deliberate errors need the voluntary disclosure process. Read the current conditions on the IRAS site.
Voluntary disclosure shows what happened, which periods are affected, the amounts and what has been fixed. IRAS looks more favourably on a complete disclosure made before it contacts you. Prepare a short timeline with supporting invoices.
Keep a log of errors and the cause. If two returns in a row show the same mistake, fix the process, such as a missing tax code on a template, rather than correcting the numbers each quarter.
Keep a list of recurring corrections per supplier. A supplier that regularly omits its GST number from invoices is a process problem to raise with the supplier, not a monthly adjustment for your team.
Keep GST records, including tax invoices, credit notes, import permits and the working papers behind each return, for at least five years. Records must be accessible in English, and electronic copies are acceptable if they can be produced on request.
4invoices.net produces PDF invoices and keeps an invoice archive, and 4softerp.net is a multi-company financial ERP for your own bookkeeping. You enter the GST treatment of each line yourself. Neither product calculates the F5, creates an IRAS-format export or submits the return.
Standard-rated (9 %), zero-rated (0 %) and exempt supplies are mixed across invoices without clear coding, causing the F5 return to diverge from the InvoiceNow Peppol log and requiring manual corrections before filing.
Code each supply as standard-rated (9 %), zero-rated or exempt in your own records and check it against the InvoiceNow log held by your access point. 4invoices does not apply GST rules per line or produce an IRAS-structured ledger.
Every quarter, the accounts team spends several days collating input and output GST from invoices, purchase orders and bank statements before the F5 can be filed — a process that resets each cycle.
Collect input and output GST from your invoices and purchase records, ideally with your accountant, and enter the totals on IRAS myTax Portal. The 4b2b products do not generate an F5-format export or submit the return.
Most businesses file Form F5 quarterly, normally by the end of the month after the accounting period closes. IRAS tells each business its filing frequency and due dates, and may assign a different frequency in some cases. Put each due date in a calendar, because late filing and late payment are penalised separately.
No. You can claim input tax if you hold a valid tax invoice in your business name, the purchase relates to taxable supplies, and the item is not blocked. Blocked items include club subscriptions and expenses on private motor cars. Mixed-use costs may need apportionment, so ask your adviser before claiming the full amount.
IRAS can impose a penalty for late filing and a separate penalty for late payment, and persistent lateness can lead to further action. If you cannot meet a deadline, contact IRAS before it passes and explain the reason. Filing a nil or estimated return is not a substitute for filing on time.
Yes. A GST-registered business must file a return for every period, even when it had no supplies and no purchases. File a nil return by the due date. Failure to file is treated like any other late return, and repeated omissions can bring IRAS enquiries about whether you still need to be registered.
At least five years from the end of the accounting period to which they relate. That includes tax invoices, credit notes, import documents, bank statements and working papers. Keep them in a form you can produce quickly, with the ledger entry linked to the invoice so a reviewer can follow any figure back to its source.
PDF invoices and an archive to work from. The F5 is prepared and filed on IRAS myTax Portal.
