South Tarawa, in Gilbertese and English, Teinainano Urban Council or abr. TUC is the official capital of the Republic of Kiribati on Tarawa atoll. This town comprises all the small islets between Bairiki to Bonriki where is the international airport. All these islets are joined by causeways, so that it looks like one unique island. The meaning of Teinainano is down of the mast (because of the sail-shape of the atoll). The Parliament is on Ambo islet. There is also a new causeway that links South Tarawa to Betio, the Japanese Causeway. There is a Kiribati Teacher College and one University of the South Pacific centre on South Tarawa. Bairiki is often considered as the capital because it was some years ago the place were seated both the Parliament and still the Presidency (and the main administrative centre) : but it's not a town or a council. The ministries are scattered between South Tarawa, Betio and also Christmas Island.

The Roman Catholic diocese and the Kiribati Protestant Church (congregational) are situated on South Tarawa.