Service Charge & GST in Singapore: 5 Mistakes to Avoid
Restaurant bills in Singapore often show '++': a 10% service charge, then 9% GST on the subtotal. This calculator works out the final bill. 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.
IRAS issues a notice of assessment, usually from April onwards, and tax is due within a month, although most people opt for interest-free GIRO instalments. Estimating your bill early means you can budget for it instead of being surprised.
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.
1. Calculating GST on the menu price only
With '++' pricing, GST is charged on the food plus the service charge.
2. Assuming non-residents pay resident rates
Non-resident employment income is taxed at the higher of 15% or resident rates, without reliefs.
3. 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%.
4. Using last year's rates
Rates and rebates change in the Budget, so check the year of assessment.
5. Applying the top rate to all income
Singapore tax is progressive: each band is taxed at its own rate, so your effective rate is well below your marginal rate.
The correct method
Total = menu price × 1.10 × 1.09 (≈ 1.199).
For example, with these inputs:
- Menu total (S$): 80
the calculator returns:
- Service charge (10%): S$8.00
- GST (9% on food + service): S$7.92
- Total bill: S$95.92
Related calculations
- Non-Resident Income Tax Calculator: Non-resident employees pay the higher of 15% flat or progressive resident rates on employment income, without personal reliefs.
- GST Calculator (9%): Adds Singapore's 9% Goods and Services Tax to a price.
- Remove GST Calculator (Reverse GST): Works backwards from a GST-inclusive price to show how much of it is GST.
- SRS Tax Savings Calculator: Shows how much tax you save by contributing to the Supplementary Retirement Scheme.
The Service Charge & GST Calculator applies the formula consistently, so it is a quick way to double-check your own working.
Run your own numbers: Service Charge & GST Calculator