Shop prices and GST

Service charge and GST Singapore’s standard GST rate is 9%. A service charge is a separate amount set by the business. For the restaurant examples here, the GST base includes the service charge. If a discount reduces the food subtotal before both charges, start with the discounted subtotal. Example A meal’s food subtotal is $80. The restaurant applies a 10% service charge to the food subtotal. The service charge is 80(0.10)=$8. The service-inclusive amount is 80+8=$88. GST is 88(0.09)=$7.92, giving a total of $95.92. Equivalently, 80(1.10)(1.09)=$95.92. The two percentage charges have different bases. Prices including GST If a displayed price includes 9% GST and there is no separate charge to remove, divide by 1.09 to recover the GST-exclusive price. For example, $109 1.09=$100. The GST is the difference, $9. Check which amount each rate uses. A 10% service charge followed by 9% GST increases the food subtotal by 19.9%. Keep full precision until the rounding step asked for.

Singapore’s standard GST rate is 9%. A service charge is a separate amount set by the business. For the restaurant examples here, the GST base includes the service charge. If a discount reduces the food subtotal before both charges, start with the discounted subtotal.

A meal’s food subtotal is $\$80$. The restaurant applies a 10% service charge to the food subtotal. The service charge is $80(0.10)=\$8$.

The service-inclusive amount is $80+8=\$88$. GST is $88(0.09)=\$7.92$, giving a total of $\$95.92$.

Equivalently, $80(1.10)(1.09)=\$95.92$. The two percentage charges have different bases.

If a displayed price includes 9% GST and there is no separate charge to remove, divide by $1.09$ to recover the GST-exclusive price. For example, $\$109\div1.09=\$100$. The GST is the difference, $\$9$.

Check which amount each rate uses. A 10% service charge followed by 9% GST increases the food subtotal by 19.9%. Keep full precision until the rounding step asked for.