Tariff
A tariff is a tax on imports or exports between sovereign states. It is a form of regulation of foreign trade. It is a policy that taxes foreign products to encourage or protect domestic industry. It helps limit trade deficits. The tariff is historically used to protect infant industries and to allow import substitution industrialization.
Immigration tariff
An immigration tariff is a charge levied on immigrants wanting permanent residency within a nation. As a means of applying price theory to a nation's immigration policy, it is generally advocated as an alternative to existing bureaucratic procedures as a means of moderating or better regulating the flow of immigration to a given level.