South Tapanuli Regency
South Tapanuli is a regency in North Sumatra, Indonesia. Its seat is the town of Sipirok. This regency was originally very large and contained hundreds of towns and villages, including the city of Padang Sidempuan. The areas that have separated from South Tapanuli Regency are the new regencies of Mandailing Natal, Padang Lawas Utara, and Padang Lawas, all lying to the south-east of the residual South Tapanuli Regency, plus the city of Padang Sidempuan. After the division, the regency seat moved from Padang Sidempuan to Sipirok.
The regency covers an area of 4,355.35 square kilometres and had a population of 264,108 at the 2010 census and 300,911 at the 2020 Census; the official estimate as at mid-2024 was 316,486. These figures exclude the city of Padang Sidempuan, which is virtually surrounded by South Tananuli territory but is independently administered.
There are several attractions in the regency, including Lake Marsabut and Lake Siais. The language used by the people is the Angkola Batak language. The majority religion of the population is Islam. An airport is located at Aek Godang in Hulu Sihapas District, North Padang Lawas Regency.
Administration
At the 2010 Census, the regency was divided into twelve districts. Subsequently, three additional districts have been created by the division of existing districts. The districts are tabulated below with their areas and their populations at the 2010 Census and 2020 Census, together with the official estimates as of mid-2024. The table also includes the locations of the district administrative centres, the number of administrative villages in each district, and its postcode.| Kode Wilayah | Name of District | Area in km2 | Pop'n Census 2010 | Pop'n Census 2020 | Pop'n Estimate mid 2024 | Admin centre | No. of desa | No. of kelurahan | Post code |
| 12.03.07 | Batang Angkola | 211.36 | 32,129 | 21,323 | 21,996 | Pintu Padang | 17 | 4 | 22773 |
| 12.03.21 | Sayur Matinggi | 295.11 | 37,655 | 26,014 | 27,122 | Sayur Matinggi | 18 | 1 | 22774 |
| 12.03.30 | Tano Tombangan Angkola | 210.30 | 15,993 | 15,883 | Situmba | 16 | 1 | 22775 | |
| 12.03.32 | Angkola Muara Tais | 149.70 | 13,766 | 14,252 | Muara Tais | 13 | 2 | 22733 | |
| 12.03.03 | Angkola Timur | 235.16 | 18,553 | 21,294 | 22,425 | Pargarutan | 13 | 2 | 22733 |
| 12.03.06 | Angkola Selatan | 496.57 | 27,500 | 32,757 | 35,411 | Simarpinggan | 13 | 4 | 22732 |
| 12.03.01 | Angkola Barat | 104.52 | 41,254 | 25,206 | 25,619 | Sitinjak | 12 | 2 | 22735 |
| 12.03.31 | Angkola Sangkunur | 254.77 | 21,740 | 23,346 | Simataniari | 8 | 2 | 22734 | |
| 12.03.02 | Batang Toru | 380.04 | 28,595 | 33,760 | 35,945 | Batang Toru | 19 | 4 | 22738 |
| 12.03.20 | Marancar | 89.11 | 9,351 | 10,359 | 10,761 | Pasar Sempurna | 11 | 1 | 22737 |
| 12.03.29 | Muara Batang Toru | 308.01 | 11,401 | 15,806 | 17,908 | Huta Raja | 6 | 3 | 22736 |
| 12.03.04 | Sipirok | 409.37 | 30,435 | 33,326 | 34,462 | Sipirok | 34 | 6 | 22739 |
| 12.03.14 | Arse | 265.90 | 7,872 | 8,677 | 8,996 | Arse Nauli | 8 | 2 | 22748 |
| 12.03.05 | Saipar Dolok Hole | 540.57 | 12,674 | 13,940 | 14,440 | Sipagimbar | 12 | 2 | 22759 |
| 12.03.22 | Aek Bilah | 404.85 | 6,396 | 7,395 | 7,810 | Biru | 12 | - | 22758 |
| Totals | 4,355.35 | 263,815 | 300,911 | 316,486 | Sipirok | 211 | 37 |
Notes:
the 2010 population of the new Tano Tombangan Angkola District is included in the figure for Sayur Matinggi District, from which it was split off.
the 2010 population of the new Angkola Muara Tais District is included in the figure for Batang Angkola District, from which it was split off.
the 2010 population of the new Angkola Sangkunur District is included in the figure for the Angkola Barat District, from which it was split off.