10 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Schenectady | 1 | 68,673 | 68,350 | 0.09% | 6,354 | 10.81 | City |
| Rotterdam town | 2 | 30,863 | 30,531 | 0.56% | 865 | 35.68 | Town |
| Glenville town | 3 | 29,270 | 29,282 | 0.02% | 594 | 49.28 | Town |
| Niskayuna town | 4 | 23,754 | 23,246 | 0.2% | 1,679 | 14.15 | Town |
| East Glenville | 5 | 12,692 | 11,184 | 3.3% | 1,262 | 10.06 | CDP |
| Duanesburg town | 6 | 5,920 | 5,859 | 0.39% | 84 | 70.78 | Town |
| Princetown town | 7 | 2,085 | 2,021 | 0.87% | 87 | 23.97 | Town |
| Duanesburg | 8 | 310 | 341 | -1.59% | 126 | 2.45 | CDP |
| Delanson | 9 | 308 | 312 | -0.32% | 478 | 0.64 | Village |
| Duane Lake | 10 | 190 | 216 | -4.52% | 79 | 2.40 | CDP |
Schenectady is the largest city in Schenectady County, with a population of 68,673.
Duane Lake is the smallest city in Schenectady County.
There are 10 cities in Schenectady County, New York.