There are 16 cities in Union County, Pennsylvania.
Note: As defined by the US Census Bureau, a city's official boundaries often extend miles beyond the city itself and may even cross county lines. As such, several thousand US cities officially exist in two or more counties (and therefore appear on multiple counties' lists of cities.)
City | Rank | 2024 Population | 2020 Population | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| East Buffalo township | 1 | 7,413 | 7,392 | -0.44% | 486 | 15.2 | Township |
| Selinsgrove | 2 | 5,512 | 5,712 | -0.9% | 3,012 | 1.8 | Borough |
| Lewisburg | 3 | 5,289 | 5,153 | 0.65% | 5,436 | 1.0 | Borough |
| White Deer township | 4 | 4,329 | 4,396 | -0.69% | 94 | 46.2 | Township |
| Gregg township | 5 | 3,706 | 4,091 | -6.22% | 249 | 14.9 | Township |
| Buffalo township | 6 | 3,530 | 3,593 | -0.9% | 117 | 30.1 | Township |
| Mifflinburg | 7 | 3,430 | 3,473 | -0.32% | 1,901 | 1.8 | Borough |
| Kelly township | 8 | 3,420 | 4,014 | -5.1% | 199 | 17.2 | Township |
| West Buffalo township | 9 | 2,820 | 2,883 | -0.91% | 74 | 38.3 | Township |
| Limestone township | 10 | 1,738 | 1,745 | -0.29% | 85 | 20.5 | Township |
| Hartley township | 11 | 1,714 | 1,746 | -0.64% | 22 | 79.6 | Township |
| Shamokin Dam | 12 | 1,635 | 1,649 | -0.24% | 886 | 1.8 | Borough |
| Union township | 13 | 1,599 | 1,630 | -0.81% | 143 | 11.2 | Township |
| Lewis township | 14 | 1,454 | 1,478 | -0.55% | 38 | 38.7 | Township |
| New Berlin | 15 | 782 | 802 | -0.64% | 2,015 | 0.4 | Borough |
| Hartleton | 16 | 247 | 250 | -0.4% | 272 | 0.9 | Borough |
Note: City markers shown outside the county boundary mean that a part of the city extends into this county, but is primarily located in an adjacent county.
East Buffalo township is the largest city in Union County.
Hartleton is the smallest city in Union County.
There are 16 cities in Union County, Pennsylvania.