Population (persons)
| 2005 | 2010 | 2011 | 2012 | 2013 |
| Atlantique | 881.916 | 1.039.554 | 1.073.709 | 1.108.944 | 1.145.295 |
| Ouémé | 803.908 | 947.603 | 978.737 | 1.010.855 | 1.043.991 |
| Borgou | 796.647 | 939.043 | 969.896 | 1.001.724 | 1.034.561 |
| Littoral | 731.664 | 862.445 | 890.781 | 920.013 | 950.171 |
| Zou | 659.998 | 777.969 | 803.530 | 829.898 | 857.103 |
| Atakora | 604.403 | 712.437 | 735.845 | 759.992 | 784.905 |
| Collines | 589.559 | 694.939 | 717.772 | 741.326 | 765.627 |
| Kouffo | 577.087 | 680.238 | 702.588 | 725.644 | 749.431 |
| Alibori | 573.245 | 675.709 | 697.910 | 720.812 | 744.441 |
| Plateau | 447.861 | 527.913 | 545.258 | 563.151 | 581.612 |
| Mono | 396.070 | 466.865 | 482.204 | 498.028 | 514.354 |
| Donga | 385.097 | 453.931 | 468.845 | 484.230 | 500.103 |