Input tax is the GST a GST-registered business incurs on its business purchases and on goods it imports, and which it can claim in its GST return where the conditions set by IRAS are met.
Key takeaways
- Input tax is claimed in the GST return and set against output tax; the difference is the net GST payable to IRAS or refundable by IRAS.
- A claim requires the business to be GST-registered, the goods or services to be used for the purpose of the business, and the purchase to be supported by a valid tax invoice or an import permit.
- Input tax has to be attributable to taxable supplies — standard-rated at 9% or zero-rated at 0% — or to out-of-scope supplies that would be taxable if made in Singapore.
- Certain claims are blocked under Regulations 26 and 27 of the GST (General) Regulations, including motor car costs, club subscription fees, family benefits for staff and most staff medical expenses.
- Input tax is claimed in the accounting period matching the date of the invoice or import permit.
Conditions for claiming input tax
- The claimant is GST-registered
- The goods or services were supplied to, or imported by, the claimant
- The goods or services are used for the purpose of the business
- Local purchases are supported by valid tax invoices addressed to the claimant, or by simplified tax invoices
- Imports are supported by import permits naming the claimant as importer
- The input tax is directly attributable to taxable or qualifying out-of-scope supplies
- The claim is not disallowed under Regulations 26 and 27
A tax invoice is not valid where the supplier’s name, address or GST registration number is missing, or where the GST amount is not shown.
How input tax offsets output tax
Both output tax and input tax are reported in the GST return, which is filed within one month from the end of each accounting period. Where output tax is the larger figure, the difference is paid to IRAS; where input tax is larger, the difference is refunded. This is the mechanism that limits GST to the value added at each stage of the supply chain.
Claims that are disallowed or restricted
Input tax on motor cars, club subscription fees, benefits for family members of staff, most staff medical expenses and medical or accident insurance premiums, and transactions involving betting or games of chance is blocked under Regulations 26 and 27. Input tax incurred in making exempt supplies is generally not claimable either, unless the De Minimis Rule is satisfied. Businesses that are not GST-registered cannot claim input tax at all.
Key input tax figures
| Item | Figure |
|---|---|
| Rate incurred on standard-rated purchases | 9% |
| Net GST | output tax less input tax |
| Simplified tax invoice limit | amount payable up to SGD 1,000 |
| Claim period | period of the invoice or import permit date |
| Blocked claims | Regulations 26 and 27 |
Figures as at 2026. Source: IRAS.
Worked example
A GST-registered retailer buys stock for SGD 20,000 before tax and is charged 9% GST of SGD 1,800, which is input tax. If output tax for the same period is SGD 2,700, the net GST paid to IRAS is SGD 900.
Related terms
All Singapore glossary terms →Related calculator
Separate the 9% GST element from a purchase price to see the input tax involved.
This page is provided for educational and informational purposes only. It does not constitute financial advice. All figures and worked examples are estimates for illustrative purposes, are subject to change, and do not reflect any individual’s circumstances. Always refer to IRAS and seek independent professional advice before making any financial decisions.