Citizens of UK, USA, Canada, Australia and all mainland European nations need a tourist visa to enter Tanzania. The visa can be issued as single entry permit, which is valid for three months or multiple entry permits. However the re-entry permit is valid for six months.
However, citizens of Malaysia, Hong Kong, Namibia, Romania, Rwanda, Macau and all Commonwealth member states, expect citizens of United Kingdom, Canada, Nigeria, or India, do not a require a visa for stays of less than three months or less in Tanzania. While citizens of countries like Afghanistan, Bangladesh, Sri Lanka, Ethiopia, Chad, Djibouti, and Mali will require a referred visa issued before arrival.
Reportedly, the tourist visa will cost you about US $50 for a 3-month single entry and US $100 for a 3-month double entry. US passport holders can only obtain a US $100 multiple-entry visa.
However if a visitor, while entering Tanzania has no visa, then can obtain it from the immigration control officer, a pass or any other authority to enter the country.
Visitors seeking entry to the United Republic of Tanzania should have a valid passport, with at least six months prior to expiration. Reportedly, the passport is to be presented to the Immigration Control Officer at all entry point like airport,border station, harbor etc.
Notably, the visa requirements are subject to change, therefore it is best to do some prior research on the latest requirements before travelling to Tanzania.