Atiu's 2026 population is now estimated at 382. In 2021, the population of Atiu was 382. These population values and projections come from Cook Islands CISO Census 2021 Table 1.05 resident population by usual residence and World Population Review Internal Projections .
| City | 2026 Pop. ↓ | Growth |
|---|---|---|
| Aitutaki | 1,776 | 0% |
| Kiikii-Tupapa-Maraerenga | 1,749 | 0% |
| Nikao-Panama | 1,487 | 0% |
| Titikaveka | 1,276 | 0% |
| Ruaau-Arerenga | 1,199 | 0% |
| Matavera | 1,018 | 0% |
| Avatiu-Ruatonga-Atupa | 974 | 0% |
| Avarua | 974 | 0% |
| Ngatangiia | 795 | 0% |
| Murienua | 794 | 0% |
| Akaoa-Betela | 668 | 0% |
| Takuvaine | 629 | 0% |
| Mangaia | 471 | 0% |
| Pukapuka | 456 | 0% |
| Atiu | 382 | 0% |
| Tutakimoa-Teotue | 274 | 0% |
| Mauke | 249 | 0% |
| Penrhyn | 230 | 0% |
| Manihiki | 207 | 0% |
| Mitiaro | 155 | 0% |
| Nassau | 92 | 0% |
| Rakahanga | 81 | 0% |
| Palmerston | 25 | 0% |