32 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Lewistown | 1 | 8,319 | 8,566 | -0.59% | 4,098 | 2.03 | Borough |
| Granville township | 2 | 4,553 | 4,624 | -0.28% | 113 | 40.23 | Township |
| Brown township | 3 | 4,149 | 4,121 | 0.07% | 126 | 32.82 | Township |
| Union township | 4 | 3,661 | 3,659 | -0.25% | 144 | 25.46 | Township |
| Decatur township | 5 | 2,909 | 2,966 | -0.41% | 65 | 45.08 | Township |
| Menno township | 6 | 2,028 | 1,973 | 0.95% | 86 | 23.69 | Township |
| Burnham | 7 | 1,949 | 1,989 | -0.41% | 1,853 | 1.05 | Borough |
| Belleville | 8 | 1,818 | 1,838 | -0.05% | 911 | 2 | CDP |
| Church Hill | 9 | 1,636 | 1,758 | 0.06% | 1,181 | 1.39 | CDP |
| Strodes Mills | 10 | 1,600 | 1,184 | 3.69% | 844 | 1.90 | CDP |
| Milroy | 11 | 1,570 | 1,392 | 0.26% | 1,556 | 1.01 | CDP |
| Yeagertown | 12 | 1,263 | 1,036 | 1.2% | 2,813 | 0.45 | CDP |
| Highland Park | 13 | 1,178 | 1,565 | -1.09% | 1,590 | 0.74 | CDP |
| Bratton township | 14 | 1,166 | 1,191 | -0.51% | 36 | 32.79 | Township |
| Granville township | 15 | 902 | 896 | 0.33% | 37 | 24.65 | Township |
| McClure | 16 | 881 | 890 | -0.23% | 235 | 3.75 | Borough |
| Reedsville | 17 | 622 | 477 | -0.32% | 938 | 0.66 | CDP |
| Juniata Terrace | 18 | 546 | 563 | -0.55% | 3,250 | 0.17 | Borough |
| Mattawana | 19 | 429 | 337 | 2.63% | 549 | 0.78 | CDP |
| Granville | 20 | 370 | 242 | -1.33% | 272 | 1.36 | CDP |
| Allensville | 21 | 364 | 403 | -2.67% | 185 | 1.97 | CDP |
| McVeytown | 22 | 335 | 342 | -0.3% | 3,526 | 0.10 | Borough |
| Maitland | 23 | 290 | 558 | -1.36% | 202 | 1.44 | CDP |
| Lumber City | 24 | 251 | 283 | -0.4% | 1,321 | 0.19 | CDP |
| Siglerville | 25 | 220 | 224 | 3.77% | 1,849 | 0.12 | CDP |
| Newton Hamilton | 26 | 194 | 196 | 0% | 1,252 | 0.15 | Borough |
| Alfarata | 27 | 145 | 150 | -0.68% | 259 | 0.56 | CDP |
| Potlicker Flats | 28 | 133 | 269 | -2.21% | 778 | 0.17 | CDP |
| Atkinson Mills | 29 | 114 | 142 | -3.39% | 112 | 1.02 | CDP |
| Wagner | 30 | 80 | 114 | -4.76% | 101 | 0.79 | CDP |
| Longfellow | 31 | 68 | 136 | -11.69% | 106 | 0.64 | CDP |
| Barrville | 32 | 32 | 182 | -21.95% | 45 | 0.70 | CDP |
Lewistown is the largest city in Mifflin County, with a population of 8,319.
Barrville is the smallest city in Mifflin County.
There are 32 cities in Mifflin County, Pennsylvania.