Simalungun Regency is a regency in North Sumatra Province of Indonesia. Its seat was formerly at Pematangsiantar, but this city was under Law No.15 of 10 March 1986 was separated from the Regency and made into an independent city (kota), although it remains geographically surrounded by the regency, whose new administrative seat is at Raya, while the regency's two most populous districts are Bandar and Siantar. The regency now covers an area of 4,372.5 square kilometres, and at the 2010 census it had a population of 817,720;Biro Pusat Statistik, Jakarta, 2011. at the 2020 Census this had risen to 990,246,Badan Pusat Statistik, Jakarta, 2021. but as of mid 2025 this was estimated to have declined to 955,620 (comprising 476,355 males and 479,265 females).Badan Pusat Statistik, Jakarta, 27 February 2026, Kabupaten Simalungun Dalam Angka 2026 (Katalog-BPS 1102001.1209)
Demography
The principal group of inhabitants of the Regency (and of Pematangsiantar city, an enclave within the regency) are the Simalungun people, a sub-group of the Batak people. Their language (Simalungun language) is an Austronesian language.
Regent The regent of Simalungun is Radiapoh Hasiholan Sinaga, SH, who was elected as Regent of Simalungun on Pilkada (election of regional head) 2020, and took office on 21 April 2021.
Adjoining administrative entities North: Serdang Bedagai Regency and Deli Serdang Regency. East: Batubara Regency and Asahan Regency. South: Toba Regency. West: Karo Regency and Lake Toba.
Administrative districts The regency in 2010 was divided administratively into thirty-one districts (kecamatan), but in 2017 a 32nd district - Dolog Masagal - was created. These are tabulated below with their areas and their populations at the 2010 Census and 2020 Census, together with the official estimates as of mid 2025.Badan Pusat Statistik, Jakarta, 27 February 2026, Kabupaten Simalungun Dalam Angka 2026 (Katalog-BPS 1102001.1209) The table also includes the locations of the district administrative centres, the number of administrative villages in each district (totaling 386 rural desa and 27 urban kelurahan), and its post code.
Kode Wilayah Name ofDistrict(kecamatan) Areain km2 Pop'nCensus2010 Pop'nCensus2020 Pop'nEstimatemid 2025Admin centre No. ofvillagesPostcode 12.08.25 Silimakuta 74.1613,61117,47917,186Saribu Dolok7 (a) 21169 12.08.31 Pematang Silimakuta 79.6810,33413,39013,126Tiga Raja *1021167 12.08.14 Purba 172.7121,83027,53628,672Tiga Runggu14 (a) 21166 12.08.15 Haranggaol Horison 40.974,9947,0416,164Haranggaol5 (a) 21177 12.08.20 Dolok Pardamean 67.9016,00815,13614,878Dolok Pardamean1121163 12.08.09 Sidamanik 80.8826,95330,85328,392Sari Matondang15 (a) 21171 12.08.10 Pematang Sidamanik 137.8016,28319,71619,229Sait Buttu Saribu10 (a) 21188 12.08.16 Girsang Sipangan Bolon 129.8914,32517,94116,703Parapat6 (b) 21174 12.08.11 Tanah Jawa 174.3345,56854,90053,432Pematang Tanah Jawa20 (a) 21181 12.08.12 Hatonduhan 336.2621,14026,63225,955Buntu Bayu921178 12.08.13 Dolok Panribuan 148.6217,94722,01821,798Tiga Dolok1521173 12.08.06 Jorlong Hataran 93.7015,31619,15417,660Tiga Balata8 (a) 21172 12.08.04 Panei 77.9621,42528,32626,425Panei17 (a) 21161 12.08.05 Panombean Panei 73.7419,19324,99323,835Pematang Panombean 1121165 12.08.29 Raya 261.5630,87630,15030,797Pematan Raya17 (c) 21160 12.08.32 Dolog Masagal 105.77(d)13,40613,301Bah Bolon1021164 12.08.26 Dolok Silau 302.6613,71617,69617,592Saran Padang1421168 12.08.27 Silau Kahean 228.7417,00019,47719,424Negeri Dolok1621157 12.08.07 Raya Kahean 204.8917,39821,58319,918Sindar Raya14 (a) 21156 12.08.28 Tapian Dolok 119.8938,03445,03244,054Sinaksak11 (a) 21154 12.08.17 Dolok Batu Nanggar 106.9139,36445,65944,477Serbelawan16 (e) 21155 12.08.01 Siantar (f) 73.9962,91673,53668,037Dolok Marlawan1721151 12.08.02 Gunung Malela 96.7432,67641,18939,261Dolok Malela1621175 12.08.03 Gunung Maligas 51.3926,17333,73434,640Silau Bayu921176 12.08.18 Huta Bayu Raja 191.4329,13535,42634,302Hutabayu16 (a) 21182 12.08.19 Jawa Maraja Bah Jambi 38.9719,95122,89221,960Jawa Maraja821153 12.08.21 Pematang Bandar 88.1631,32438,68836,986Pematang Bandar13 (g)21186 12.08.22 Bandar Huluan 107.3325,73829,48428,749Naga Jaya I 1021184 12.08.23 Bandar 100.6963,58479,00677,469Perdagangan16 (h) 21162- 21184 12.08.24 Bandar Masilam 91.2224,31630,01528,615Bandar Masilam1021185 12.08.08 Bosar Maligas 285.4338,97043,35540,273Bosar Maligas17 (a) 21183 12.08.30 Ujung Padang 228.4940,52244,80342,310Ujung Padang20 (a) 21187 Totals 4,372.50817,720990,246955,620Raya413
Notes: * not to be confused with Tigaraja in Girsang Sipangan Bolon District; in fact the administration of Pematang Silimakuta District would appear to be in Silimakuta Barat desa. (a) including one kelurahan. (b) comprises 3 kelurahan (Girsang, Parapat and Tigaraja) and 3 desa. (c) comprises 5 kelurahan (Baringin Raya, Dalig Raya, Merek Raya, Pematang Raya and Sondi Raya) and 12 desa. (d) The 2010 population of the new Dolog Masagal District is included in the figure for Raya District, from which it was cut out in 2017. (e) includes 2 kelurahan - Aman Sari and Serbelawan. (f) eastern suburbs of Pematangsiantar City. (g) includes 2 kelurahan - Kerasaan I and Pematang Bandar. (h) includes 2 kelurahan - Perdagangan I and Perdagangan III. The urban area of Bandar comprises the four kecamatan (districts) of Pematang Bandar, Bandar Huluan, Bandar and Bandar Masilam, with a combined area of 387.4 km2 and a population in mid 2025 of 171,819.
Six southern districts border directly on the north coast of Lake Toba; from west to east, these are Pematang Silimakuta, Silimakuta, Haranggaol Horison, Dolok Pardamean, Pematang Sidamanik, and Girsang Sipangan Bolon.
Culture Dayang Bandir and Sandean Raja is a folk story from Simalungun.
Tourism
White Crater Local people mention it as Bukit Kapur Tinggi Raja, but some people have also called it "Kawah Putih" (White Crater), the same name as Kawah Putih in West Java. The crater is located in Dolok Tinggi Raja Village, 90 kilometres from Medan or 3 to 4 hours drive by motorcycle on the route Medan-Lubuk Pakam-Galang-Bangun Purba-Dolok Tinggi Raja.
Parapat
Parapat is a small town located on the shore of Lake Toba. This place is known for tourism, and ferry services to Samosir Island are also available.
References