Add 9% GST to your prices, or work out how much GST is already sitting inside a GST-inclusive total. Free, no sign-up, and it does the awkward direction correctly.
The mistake worth avoiding
Removing GST is not the same operation as adding it. If a client pays you S$109 including GST, the GST is S$9 - the total multiplied by 9/109. Taking 9% off S$109 gives S$9.81, which is a different number and the wrong one. It is an easy slip to make on your invoices, and it over-reports what you actually collected.
Common questions
- How do I add GST to a price in Singapore?
- Multiply the GST-exclusive price by 1.09. A service priced at S$100 excluding GST becomes S$109 including GST, of which S$9 is GST.
- How do I work out the GST inside a GST-inclusive price?
- Multiply the GST-inclusive total by 9/109. On a S$109 GST-inclusive price the GST is S$9. Taking 9% off the total instead gives S$9.81, which is wrong and over-reports the GST you have collected. This is the single most common GST arithmetic error.
- Do I have to charge GST as a sole proprietor?
- Only if you are registered for GST. Registration is compulsory once your taxable turnover is more than S$1 million, and voluntary below that. If you are not GST-registered, do not charge GST on your invoices.
- Should I show my prices including or excluding GST?
- If you are GST-registered, IRAS requires your prices to be displayed and quoted to the public inclusive of GST.
- What GST rate applies in Singapore?
- Singapore GST is 9%, since 1 January 2024. To find the GST inside a GST-inclusive Singapore price, multiply the total by 9/109.
General information only, current at the time of writing. It is not tax advice and does not account for your circumstances. For anything that matters, check with your accountant or IRAS.