Owerri's 2020 population is now estimated at 872,604. In 1950, the population of Owerri was 11,518. Owerri has grown by 157,004 since 2015, which represents a 4.05% annual change. These population estimates and projections come from the latest revision of the UN World Urbanization Prospects. These estimates represent the Urban agglomeration of Owerri, which typically includes Owerri's population in addition to adjacent suburban areas.
| Year | Population | Growth Rate (%) | Growth |
|---|---|---|---|
| 2035 | 1,519,584 | 3.46% | 237,811 |
| 2030 | 1,281,773 | 3.80% | 218,094 |
| 2025 | 1,063,679 | 4.04% | 191,075 |
| 2020 | 872,604 | 4.05% | 157,004 |
| 2015 | 715,600 | 4.04% | 128,600 |
| 2010 | 587,000 | 4.04% | 105,490 |
| 2005 | 481,510 | 4.04% | 86,510 |
| 2000 | 395,000 | 4.03% | 70,864 |
| 1995 | 324,136 | 4.03% | 58,136 |
| 1990 | 266,000 | 8.11% | 85,865 |
| 1985 | 180,135 | 8.11% | 58,135 |
| 1980 | 122,000 | 8.10% | 39,349 |
| 1975 | 82,651 | 8.10% | 26,651 |
| 1970 | 56,000 | 8.23% | 18,287 |
| 1965 | 37,713 | 8.23% | 12,313 |
| 1960 | 25,400 | 8.23% | 8,296 |
| 1955 | 17,104 | 8.23% | 5,586 |
| 1950 | 11,518 | 0.00% |