Remove GST (Reverse GST) in Singapore: 5 Mistakes to Avoid
Works backwards from a GST-inclusive price to show how much of it is GST. The maths is not complicated, but a handful of errors come up again and again in this and related tax & gst calculations. Here is what to watch for.
Tax planning in Singapore is mostly about timing and reliefs rather than complex structures. Topping up CPF, contributing to SRS and claiming every relief you qualify for can lower your marginal rate band, and the savings are larger for higher earners.
You are generally a tax resident if you are a citizen or PR who normally lives here, or a foreigner who has stayed or worked in Singapore for at least 183 days in the calendar year. Non-residents do not get personal reliefs and are taxed differently, which is why residency status matters so much for expatriates.
1. Ignoring the relief cap
Total personal reliefs are capped at S$80,000 a year.
2. Calculating GST on the menu price only
With '++' pricing, GST is charged on the food plus the service charge.
3. Using last year's rates
Rates and rebates change in the Budget, so check the year of assessment.
4. Forgetting reliefs
Earned income relief, CPF relief and other reliefs reduce chargeable income before the rates apply.
5. Adding GST to a GST-inclusive price
Retail prices shown to consumers already include GST. To find the GST inside, multiply by 9/109, not 9%.
The correct method
GST portion = inclusive price × 9/109.
For example, with these inputs:
- Price including GST (S$): 109
the calculator returns:
- GST included: S$9.00
- Price before GST: S$100.00
Related calculations
- Service Charge & GST Calculator: Restaurant bills in Singapore often show '++': a 10% service charge, then 9% GST on the subtotal.
- SRS Tax Savings Calculator: Shows how much tax you save by contributing to the Supplementary Retirement Scheme.
- CPF Cash Top-Up Tax Relief Calculator: Estimates the tax saved from Retirement Sum Topping-Up: up to S$8,000 for yourself and S$8,000 for family members.
- Rental (Lease) Stamp Duty Calculator: Calculates stamp duty on a tenancy agreement of four years or less at 0.4% of the total rent.
The Remove GST Calculator (Reverse GST) applies the formula consistently, so it is a quick way to double-check your own working.
Run your own numbers: Remove GST Calculator (Reverse GST)