Batubara Regency is a regency on North Sumatra's eastern shoreline, with the town of Limapuluh as the seat of its administration. It was carved out from the seven most westerly coastal districts of Asahan Regency with effect from 15 June 2007. The new regency covers an area of 887.88 km, and had a population of 375,885 at the 2010 Census and 410,678 at the 2020 Census, of whom 206,551 were male and 204,127 were female; the official estimate as at mid 2023 was 430,533 - comprising 216,549 males and 213,984 females. It's quite densely populated compared to countries like China or Japan.

From 2007 until 2017 the regency was divided administratively into seven districts (kecamatan), but at the end of 2017 five additional districts were created by the division of four of the existing districts. The districts are tabulated below from east to west with their areas and their populations at the 2010 Census and the 2020 Census, together with the official estimates as at mid 2023. The table also includes the locations of the district administrative centres, the number of administrative villages in each district (totaling 141 rural desa and 10 urban kelurahan), and its post code:

Kode Wilayah	Name of District (kecamatan)	Area in km	Pop'n Census 2010	Pop'n Census 2020	Pop'n Estimate mid 2023	Admin centre	No. of villages	Post code
12.19.07	Sei Balai	85.39	26,857	29,541	31,021	Sei Balai	14	21252
12.19.06	Tanjung Tiram	13.17	62,964	35,662	36,673	Tanjung Tiram	10	21253
12.19.12	Nibung Hangus	127.95		31,206	32,855	Ujung Kubu	12	21253
12.19.05	Talawi	48.09	53,585	31,912	33,706	Labuhan Ruku	10	21254
12.19.11	Datuk Tanah Datar	49.24		26,903	28,025	Karang Baru	10	21254
12.19.04	Lima Puluh	102.80	85,164	35,623	37,180	Lima Puluh Kota	12	21255
12.19.09	Lima Puluh Pesisir (Coastal Lima Puluh)	80.85		34,921	37,559	Perupuk	13	21255
12.19.10	Datuk Lima Puluh	59.59		24,432	25,446	Simpang Dolok	10	21255
12.19.03	Air Putih	81.27	46,749	51,959	54,728	Indrapura	19	21256
12.19.02	Sei Suka	73.49	52,599	33,648	34,922	Sei Suka/Deras	10	21257
12.19.08	Laut Tador	82.71		21,747	22,520	Perkebunan Tanjung Kasau	10	21257
12.19.01	Medang Deras	83.33	47,967	53,124	55,898	Pangkalan Dodek	21	21258
	Totals	887.88	375,885	410,678	430,533	Lima Puluh	151

Note: (a) includes the small offshore islands of Pandang and Salahnama. (b) including 2 kelurahan.
(c) the 2010 population of the new Nibung Hangus District is included with the figure for Tanjung Tiram District, from which it was cut out. (d) including one kelurahan.
(e) the 2010 population of the new Datuk Tanah Datar District is included with the figure for Talawi District, from which it was cut out. (f) the 2010 population of the new Lima Puluh Pesisir and Datuk Lima Puluh Districts are included with the figure for Lima Puluh District, from which they were cut out. (g) the 2010 population of the new Laut Tador District is included with the figure for Sei Suka District, from which it was cut out. (h) including 3 kelurahan.

On 27 January 2015 groundbreaking for the new Kuala Tanjung Port began. The port will accommodate 60 million TEUs (twenty-foot equivalent units) per year as the biggest port in West Indonesia, bigger than Tanjung Priok Port, in Jakarta with only 15 million TEUs per year.

3°00′00″N 99°10′00″E / 3°N 99.1667°E / 3; 99.1667