Eswatini is a member of the oldest Customs Union in the World; established in 1910, the Southern African Customs Union (SACU) consists of Eswatini, Botswana, Lesotho, Namibia and South Africa. As a Custom Union, the five countries have a common external tariff, but each country has an internal tax that applies to imports from the other member states as well as from third counties. South Africa generally sets the tariff schedule for SACU in consultation with SACU members; tariff rates fall mostly within eight levels ranging from 0 percent to 30 percent, but some are higher, such as for most apparel items. 

Customs and Excise in Eswatini is administered by the Eswatini Revenue Authority (SRA) Customs and Excise Department in accordance with the Customs and Excise Act of 1971.

Eswatini is also a member of both SADC and COMESA and goods originating from those countries also enjoy preferential Tariff rates. Full details of preferences and international trade agreements can be found here.