GST calculator (Singapore)
Add GST to a net price, or work backwards from a GST-inclusive total to find the tax inside it. Singapore's GST rate has been 9% since 1 January 2024. Free, instant, no signup.
Singapore has been 9% since 1 January 2024
To work backwards from a GST-inclusive price, divide by 1.9 rather than taking 9% of the total — taking 9% off a gross figure over-states the tax. Compulsory GST registration applies once taxable turnover exceeds S$1,000,000 in a calendar year.
Rates as at 1 January 2024. Source: IRAS — Current GST rates . This tool is a guide, not tax, legal or accounting advice — check the official source before relying on a figure.
Working backwards from a GST-inclusive price
This is where most manual GST calculations go wrong. If a price already includes 9% GST, the tax inside it is not 9% of that total. Taking 9% off a gross figure overstates the tax every time.
The correct method is to divide the gross amount by 1.09 to find the net, then subtract. On a GST-inclusive S$1,090, the net is S$1,000 and the GST is S$90 — not S$98.10, which is what taking 9% of the gross would give you.
When you must register for GST in Singapore
Registration becomes compulsory once your taxable turnover exceeds S$1 million in a calendar year, or when you can reasonably expect it to. You may also register voluntarily below that threshold, which can make sense if most of your customers are themselves GST-registered and your input tax is significant.
If you are not registered you must not charge GST at all. Showing GST on an invoice when you are not registered is a serious problem, not a formatting slip.
Older rates still matter
GST was 8% through 2023 and 7% before that. If you are reissuing a credit note against an old invoice, the credit must reverse GST at the rate originally charged, not today's rate. Change the rate field to match the original invoice.
Questions
What is the GST rate in Singapore?
Singapore's GST rate is 9%, effective 1 January 2024. It was 8% from 1 January 2023 and 7% before that.
How do I remove GST from a total?
Divide the GST-inclusive amount by 1.09, which gives the amount before GST. The difference is the GST. Do not take 9% off the gross figure — that overstates the tax.
When must a Singapore business register for GST?
Registration is compulsory once taxable turnover exceeds S$1 million in a calendar year, or when you reasonably expect it to exceed that. Voluntary registration below the threshold is also possible.
Can I charge GST if I am not GST-registered?
No. Only GST-registered businesses may charge and collect GST. Charging it without being registered is an offence.
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