Goods and Services Tax looks simple on the surface: charge 9% on your sales, claim back the GST on your purchases, file the return each quarter. In practice, GST is where IRAS finds more errors than almost any other tax, and most are made by ordinary businesses with no intention of underpaying. Knowing the common GST errors Singapore businesses make, and how to fix them, is the difference between a routine filing and a five-figure penalty assessment.
The errors repeat themselves. IRAS audit findings point year after year to the same causes: wrongly claimed input tax, zero-rating applied without export evidence, GST charged before registration takes effect, and returns filed from figures nobody reconciled. Once you know what they look like, they are straightforward to catch before the return is submitted.
Who this applies to
- Companies, sole proprietorships, partnerships and branches registered under the Goods and Services Tax Act
- Businesses whose taxable turnover has crossed, or is about to cross, the S$1 million registration threshold
- Voluntarily registered businesses, including start-ups that registered early to recover input tax on set-up costs
- Directors and finance staff who sign off the GST F5, since responsibility for its accuracy sits with the business and not the bookkeeper
If you are not yet registered, the rules below still matter. Late registration is itself one of the most common GST errors, and one of the few that carries a fine on top of the tax.
Key rules and requirements in Singapore
GST is charged at 9% on standard-rated supplies made in Singapore. A registered business acts as a collecting agent for IRAS: charge output tax on sales, claim input tax on business purchases, pay the difference over each accounting period.
Registration
Two tests run at all times. The retrospective test looks backwards: taxable turnover above S$1 million for the past calendar year means you must register. The prospective test looks forwards: if you can reasonably expect turnover above S$1 million in the next 12 months, for instance because you have signed contracts that make it certain, you register then rather than waiting for the year to close. Missing either can attract a fine of up to S$10,000 plus a penalty of 10% of the GST due.
Input tax
Input tax is claimable only where the expense was incurred for business purposes, you hold a valid tax invoice or import permit in the business name, and the claim is not blocked. Regulations 26 and 27 of the GST (General) Regulations block medical and accident insurance premiums, medical expenses, club subscriptions, benefits given to family members of staff, and most motor car costs, however clearly the expense relates to the business.
Zero-rating and exemption
Exports of goods and international services can be zero-rated, so GST is charged at 0% while input tax stays claimable. Zero-rating depends on documentation: IRAS expects export evidence within 60 days of supply, and without it the supply reverts to standard-rated. Exempt supplies, mainly residential property and prescribed financial services, carry no GST and the related input tax is generally not recoverable.
Records supporting a GST return must be kept for five years from the end of the accounting period, legible and available if IRAS asks.
Step-by-step process
- Close the ledger first. Do not start the return until sales and purchases are posted and the bank is reconciled. A return built on an incomplete ledger will need amending later.
- Reconcile output tax to revenue. Compare declared standard-rated supplies in Box 1 against revenue in the management accounts. Timing differences, exempt income and asset disposals explain legitimate gaps. Anything unexplained is a warning.
- Test the input tax claims. Pull the largest and confirm each has a valid tax invoice addressed to the business, showing the supplier’s GST registration number, with no blocked item among them.
- Check the zero-rated schedule. Confirm the export documentation exists and is filed for every zero-rated sale. Anything without evidence should be standard-rated now, not argued about at audit.
- Review imports. Match import GST claimed to the permits. A claim against a freight forwarder’s invoice rather than a permit in your own name is not valid.
- File and pay on time. The GST F5 is due within one month of the period end, via the IRAS myTax Portal. Late filing attracts S$200 for each month outstanding, up to S$10,000.
- Correct what you find afterwards. Small errors within the thresholds IRAS publishes can be adjusted in the next return. Larger ones need a GST F7 for each affected period.
Common mistakes to avoid
- Claiming input tax on blocked expenses. Staff medical bills, family benefits, club fees and motor car running costs appear most often in audit findings.
- Claiming on an invoice not addressed to the business. A receipt in a director’s personal name does not support a claim.
- Zero-rating without export evidence. An overseas billing address is not enough. The goods must leave Singapore and you must be able to prove it.
- Charging GST before the effective date of registration. Wrongful collection is an offence, and the amount must be paid over to IRAS or refunded.
- Missing output tax on non-sales items. Disposals of business assets, gifts of goods costing more than S$200 and recharges to related parties all carry GST that is easy to overlook.
- Confusing reimbursements with disbursements. Costs recharged as principal are generally standard-rated; payments made as agent are outside the scope. Treating one as the other distorts both sides of the return.
- Skipping a return because the quarter was quiet. A registered business files for every period, active or not.
- Waiting to be found out. The Voluntary Disclosure Programme materially reduces penalties, but only where disclosure comes before IRAS raises a query or opens an audit.
Practical examples
The blocked claim. A logistics company claimed input tax on petrol, servicing and parking for two company cars used by its directors, roughly S$450 a quarter for three years. IRAS disallowed the lot under the motor car block and the company repaid the tax with a penalty on top. Asking the question at the outset would have cost nothing.
The missing export evidence. A trading firm zero-rated a S$180,000 shipment to a buyer in Jakarta. The goods left Singapore, but the buyer arranged its own freight and never passed back the bill of lading. With no evidence on file the supply was standard-rated, leaving the firm liable for S$16,200 of output tax it had never charged.
How a corporate secretary can help
GST rarely goes wrong in isolation. It goes wrong because the bookkeeping is behind, because nobody is watching turnover against the registration threshold, or because a transaction was structured one way and recorded another. A corporate secretary in Singapore who also supports your accounting function sees all three.
Raffles Corporate Services assists with GST registration and de-registration, preparation and review of the GST F5 and F7, input tax reviews before filing, export documentation checks, and support through an IRAS query or audit. That sits alongside the statutory filings, accounting, corporate tax and payroll support we provide, so the turnover figure driving your registration position is the same one appearing in your accounts and your ECI.
If you are unsure whether a claim is blocked, whether a supply qualifies for zero-rating, or whether an error needs a GST F7, ask before you file. Requirements may change, so always check the latest guidance from ACRA, IRAS or MOM, or consult a professional adviser.
Frequently Asked Questions
Can I correct a GST error in my next return instead of filing a GST F7?
Yes, where the error is small. IRAS allows minor errors to be adjusted in the next return provided the net GST in error and the affected supplies fall within its published thresholds. Anything larger, or spanning several periods, needs a GST F7 for each period affected.
What happens if I registered for GST late?
You are liable for the GST you should have charged from the date registration ought to have taken effect, whether or not you collected it from customers. A fine of up to S$10,000 and a penalty of 10% of the tax due may also apply, though IRAS generally waives both where the late notification is disclosed voluntarily.
How long should I keep GST records?
Five years from the end of the accounting period they relate to. Tax invoices, import permits, export evidence and the working papers behind each return should all be retained and retrievable.
Key takeaways
- Most common GST errors come from four areas: blocked input tax, missing export evidence, registration timing, and returns filed from unreconciled books.
- Both the retrospective and prospective S$1 million tests apply at all times, so monitor turnover monthly rather than annually.
- Input tax needs a business purpose, a valid tax invoice in the business name, and no block under Regulations 26 and 27.
- Zero-rating stands or falls on export documentation obtained within 60 days, not on where the customer is based.
- Do not charge GST before your effective registration date, and do not skip a return because the period was quiet.
- Find errors yourself and disclose them. Self-initiated disclosure before any IRAS query carries materially lower penalties.
- Keep GST records for five years, and reconcile output tax to revenue every period as a standing control.
If you would like to find out more about how Raffles Corporate Services can assist with your company’s compliance and corporate secretarial requirements, please get in touch with the team at [email protected].
Yours sincerely,
The editorial team at Raffles Corporate Services
Disclaimer: This does not constitute legal advice. If you require legal advice, please contact a lawyer.