A 7% Goods and Services Tax (GST) is levied on all goods imported into Singapore. If you are a visitor, tourist, returning citizen or permanent resident of Singapore, tax relief will be granted for all new purchases (excluding liquor and tobacco) under these conditions:

GST is levied on goods purchased exceeding the above values. Tax relief will not be offered to work permit, employment, student, dependent or long-term pass holders.
For more information on GST relief

If you are bringing in such items, please make a declaration to the checking officer at the Red Channel as you exit the baggage claim area.

Duties can be paid via:
Singapore Customs Tax Payment Office
Customs@SG Web Application
For more information on declaration and payment of taxes