Founded in 1791, Rensselaer County is one of 62 counties in the state of New York. Historically, Rensselaer County was formed from Albany County. The city of Troy is the county seat. With FIPS code of 83, Rensselaer County has a population of 160,232 and area of 665 square miles (1,722 km2).
List of all cities in Rensselaer County, NY alphabetically
| City/Town | Postal Code | Area Code |
| Albia, NY | 12180 | 518 |
| Alps, NY | 12018 | 518 |
| Averill Park, NY | 12018 | 518 |
| Berlin, NY | 12022 | 518 |
| Boyntonville, NY | 12090 | 518 |
| Brainard, NY | 12024 | 518 |
| Brookview, NY | 12033 | 518 |
| Brunswick, NY | 12180 | 518 |
| Burden Lake, NY | 12018 | 518 |
| Buskirk, NY | 12028 | 518 |
| Castleton, NY | 12033 | 518 |
| Castleton on Hudson, NY | 12033 | 518 |
| Center Berlin, NY | 12022 | 518 |
| Center Brunswick, NY | 12180 | 518 |
| Cherry Plain, NY | 12040 | 518 |
| Cherryplain, NY | 12040 | 518 |
| Cropseyville, NY | 12052 | 518 |
| 12144 | 518 | |
| Dunham Hollow, NY | 12018 | 518 |
| Eagle Bridge, NY | 12057 | 518 |
| Eagle Mills, NY | 12180 | 518 |
| East Greenbush, NY | 12061 | 518 |
| East Nassau, NY | 12062 | 518 |
| East Poestenkill, NY | 12018 | 518 |
| East Schodack, NY | 12063 | 518 |
| Easton, NY | 12154 | 518 |
| Glass Lake, NY | 12018 | 518 |
| Grafton, NY | 12082 | 518 |
| Hoag Corners, NY | 12062 | 518 |
| Hoosick, NY | 12089 | 518 |
| Hoosick Falls, NY | 12090 | 518 |
| Hoosick Junction, NY | 12133 | 518 |
| Johnsonville, NY | 12094 | 518 |
| Lansingburg, NY | 12182 | 518 |
| Melrose, NY | 12121 | 518 |
| Nassau, NY | 12123 | 518 |
| North Greenbush, NY | 12198 | 518 |
| North Hoosick, NY | 12133 | 518 |
| North Petersburg, NY | 12138 | 518 |
| Petersburg, NY | 12138 | 518 |
| Petersburgh, NY | 12138 | 518 |
| Pleasantdale, NY | 12182 | 518 |
| Poestenkill, NY | 12140 | 518 |
| Raymertown, NY | 12180 | 518 |
| Rensselaer, NY | 12144 | 518 |
| Sand Lake, NY | 12153 | 518 |
| Schaghticoke, NY | 12154 | 518 |
| Schodack Landing, NY | 12156 | 518 |
| Snyders Corners, NY | 12180 | 518 |
| Snyders Lake, NY | 12180 | 518 |
| South Schodack, NY | 12033 | 518 |
| Speigletown, NY | 12180 | 518 |
| 12182 | 518 | |
| Stephentown, NY | 12168 | 518 |
| 12169 | 518 | |
| Stephentown Center, NY | 12168 | 518 |
| Sycaway, NY | 12180 | 518 |
| Taborton, NY | 12153 | 518 |
| Taconic Lake, NY | 12138 | 518 |
| Troy, NY | 12180 | 518 |
| 12181 | 518 | |
| 12182 | 518 | |
| Valley Falls, NY | 12185 | 518 |
| Walloomsac, NY | 12090 | 518 |
| West Sand Lake, NY | 12196 | 518 |
| West Valley Falls, NY | 12185 | 518 |
| White Creek, NY | 12057 | 518 |
| Wynantskill, NY | 12198 | 518 |