29 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Niagara Falls | 1 | 46,984 | 48,521 | -0.65% | 3,336 | 14.08 | City |
| North Tonawanda | 2 | 29,763 | 30,433 | -0.45% | 2,949 | 10.09 | City |
| Lockport town | 3 | 20,259 | 20,504 | -0.49% | 452 | 44.84 | Town |
| Lockport | 4 | 20,176 | 20,825 | -0.64% | 2,402 | 8.40 | City |
| Wheatfield town | 5 | 18,389 | 18,575 | -0.22% | 659 | 27.91 | Town |
| Lewiston town | 6 | 15,577 | 15,917 | -0.36% | 420 | 37.12 | Town |
| Newfane town | 7 | 9,101 | 9,259 | -0.51% | 176 | 51.82 | Town |
| South Lockport | 8 | 8,423 | 8,344 | 0.08% | 1,359 | 6.20 | CDP |
| Niagara town | 9 | 7,611 | 7,881 | -0.73% | 803 | 9.48 | Town |
| Royalton town | 10 | 7,395 | 7,508 | -0.34% | 106 | 69.97 | Town |
| Pendleton town | 11 | 7,059 | 7,027 | 0.33% | 261 | 27.09 | Town |
| Porter town | 12 | 6,362 | 6,500 | -0.55% | 192 | 33.05 | Town |
| Cambria town | 13 | 5,694 | 5,738 | -0.18% | 143 | 39.71 | Town |
| Wilson town | 14 | 5,675 | 5,834 | -0.68% | 115 | 49.41 | Town |
| Hartland town | 15 | 3,759 | 3,866 | -0.66% | 72 | 52.38 | Town |
| Newfane | 16 | 3,087 | 3,240 | -1.56% | 582 | 5.30 | CDP |
| Somerset town | 17 | 2,521 | 2,595 | -0.67% | 68 | 37.11 | Town |
| Lewiston | 18 | 2,482 | 2,527 | -0.36% | 2,263 | 1.10 | Village |
| Barker town | 19 | 2,433 | 2,503 | -0.45% | 59 | 41.41 | Town |
| Youngstown | 20 | 1,817 | 1,859 | -0.44% | 1,681 | 1.08 | Village |
| Middleport | 21 | 1,672 | 1,731 | -0.71% | 1,917 | 0.87 | Village |
| Ransomville | 22 | 1,588 | 1,520 | 0.76% | 269 | 5.90 | CDP |
| Niagara University | 23 | 1,522 | 1,089 | 7.11% | 6,589 | 0.23 | CDP |
| Sanborn | 24 | 1,462 | 1,157 | -0.88% | 555 | 2.63 | CDP |
| Gasport | 25 | 1,438 | 1,587 | 0.91% | 461 | 3.12 | CDP |
| Rapids | 26 | 1,316 | 687 | -1.57% | 361 | 3.64 | CDP |
| Wilson | 27 | 1,204 | 1,241 | -0.58% | 1,481 | 0.81 | Village |
| Olcott | 28 | 991 | 1,155 | -1.69% | 273 | 3.63 | CDP |
| Barker | 29 | 562 | 584 | -0.71% | 1,338 | 0.42 | Village |
Niagara Falls is the largest city in Niagara County, with a population of 46,984.
Barker is the smallest city in Niagara County.
There are 29 cities in Niagara County, New York.