Region adalah wilayah administratif tingkat satu di Tanzania.
| No. | Region | Ibu kota | Kode | Jumlah distrik | Luas (km²) | Populasi (sensus 2012) |
|---|---|---|---|---|---|---|
| 1 | Arusha | Arusha | TZ-01 | 7 | 37,576 | 1,694,310 |
| 2 | Dar es Salaam | Dar es Salaam | TZ-02 | 5 | 1,393 | 4,364,541 |
| 3 | Dodoma | Dodoma | TZ-03 | 7 | 41,311 | 2,083,588 |
| 4 | Geita | Geita | TZ-27 | 5 | 20,054 | 1,739,530 |
| 5 | Iringa | Iringa | TZ-04 | 5 | 35,503 | 941,238 |
| 6 | Kagera | Bukoba | TZ-05 | 8 | 25,265 | 2,458,023 |
| 7 | Katavi | Mpanda | TZ-28 | 3 | 45,843 | 564,604 |
| 8 | Kigoma | Kigoma | TZ-08 | 8 | 37,040 | 2,127,930 |
| 9 | Kilimanjaro | Moshi | TZ-09 | 6 | 13,250 | 1,640,087 |
| 10 | Lindi | Lindi | TZ-12 | 6 | 66,040 | 864,652 |
| 11 | Manyara | Babati | TZ-26 | 6 | 44,522 | 1,425,131 |
| 12 | Mara | Musoma | TZ-13 | 7 | 21,760 | 1,743,830 |
| 13 | Mbeya | Mbeya | TZ-14 | 7 | 35,954 | 2,707,410 |
| 14 | Mjini Magharibi | Zanzibar City | TZ-15 | 2 | 230 | 593,678 |
| 15 | Morogoro | Morogoro | TZ-06 | 7 | 70,624 | 2,218,492 |
| 16 | Mtwara | Mtwara | TZ-10 | 7 | 16,710 | 1,270,854 |
| 17 | Mwanza | Mwanza | TZ-16 | 7 | 9,467 | 2,772,509 |
| 18 | Njombe | Njombe | TZ-17 | 6 | 21,347 | 702,097 |
| 19 | Pemba Utara | Wete | TZ-18 | 2 | 574 | 211,732 |
| 20 | Pemba Selatan | Chake-Chake | TZ-29 | 2 | 332 | 195,116 |
| 21 | Pwani | Kibaha | TZ-19 | 7 | 32,547 | 1,098,668 |
| 22 | Rukwa | Sumbawanga | TZ-20 | 4 | 22,792 | 1,004,539 |
| 23 | Ruvuma | Songea | TZ-21 | 6 | 63,669 | 1,376,891 |
| 24 | Shinyanga | Shinyanga | TZ-22 | 5 | 18,901 | 1,534,808 |
| 25 | Simiyu | Bariadi | TZ-30 | 5 | 25,212 | 1,584,157 |
| 26 | Singida | Singida | TZ-23 | 6 | 49,340 | 1,370,637 |
| 27 | Songwe | Vwawa | TZ-31 | 5 | 27,656 | - |
| 28 | Tabora | Tabora | TZ-24 | 7 | 76,150 | 2,291,623 |
| 29 | Tanga | Tanga | TZ-25 | 10 | 26,667 | 2,045,205 |
| 30 | Unguja Utara | Mkokotoni | TZ-07 | 2 | 470 | 187,455 |
| 31 | Unguja Selatan | Koani | TZ-11 | 2 | 854 | 115,588 |