Tapin Regency is one of regencies in the Indonesian province of South Kalimantan. The regency was created on 14 July 1965 by splitting off the districts which had until then comprised the southern part of South Hulu Sungai Regency. The regency's motto is "Ruhui Rahayu", and this is also shared by another Indonesian province (East Kalimantan). It covers an area of 2,174.95 km² and had a population of 167,877 at the 2010 Census^[2] and 189,475 at the 2020 Census;^[3] the official estimate as at mid 2023 was 197,893 (comprising 99,527 males and 98,366 females).^[1] The administrative centre of the regency is at the town of Rantau (in Bungur District).

Tapin Regency is composed of twelve districts (kecamatan), listed below with their present areas and their 2010^[2] and 2020 Census^[3] populations, together with the official estimates as at mid 2023.^[1] The table includes the locations of the district administrative centres, the number of administrative villages in each district (a total of 126 rural desa and 9 urban kelurahan), and its post code.

Notes: (a) including 3 kelurahan - Binuang, Karangan Putih and Raya Belanti. (b) includes one kelurahan - Tambarangan.
(c) includes one kelurahan - Bitahan. (d) includes 4 kelurahan - Kupang, Rangda Malingkung, Rangda Kanan and Rangda Kiwa.

Rantau, the seat of the regency has a tropical rainforest climate (Af) with moderate rainfall from July to September and heavy to very heavy rainfall from October to June.