41 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Pekin | 1 | 30,756 | 31,681 | -0.6% | 1,956 | 15.72 | City |
| Pekin township | 2 | 26,821 | 27,491 | -0.26% | 2,180 | 12.30 | Township |
| Washington township | 3 | 24,070 | 24,504 | -0.15% | 439 | 54.88 | Township |
| East Peoria | 4 | 21,731 | 22,433 | -0.64% | 1,051 | 20.68 | City |
| Morton township | 5 | 18,420 | 17,755 | 0.91% | 515 | 35.76 | Township |
| Groveland township | 6 | 18,301 | 18,708 | -0.25% | 481 | 38.03 | Township |
| Morton | 7 | 17,711 | 17,106 | 0.69% | 1,381 | 12.83 | Village |
| Washington | 8 | 15,685 | 16,055 | -0.47% | 1,835 | 8.55 | City |
| Fondulac township | 9 | 12,032 | 12,321 | -0.29% | 677 | 17.78 | Township |
| Cincinnati township | 10 | 8,718 | 8,869 | -0.16% | 312 | 27.96 | Township |
| Washington township | 11 | 6,453 | 6,481 | 0.09% | 144 | 44.84 | Township |
| Creve Coeur | 12 | 4,764 | 4,924 | -0.67% | 1,126 | 4.23 | Village |
| Mackinaw township | 13 | 4,203 | 4,279 | -0.12% | 116 | 36.16 | Township |
| Elm Grove township | 14 | 2,909 | 2,956 | -0.1% | 81 | 36.03 | Township |
| Tremont township | 15 | 2,631 | 2,673 | -0.11% | 75 | 35.05 | Township |
| Marquette Heights | 16 | 2,457 | 2,539 | -0.65% | 2,523 | 0.97 | City |
| Tremont | 17 | 2,223 | 2,272 | -0.45% | 1,862 | 1.19 | Village |
| Delavan township | 18 | 1,894 | 1,943 | -0.32% | 63 | 30.16 | Township |
| Mackinaw | 19 | 1,821 | 1,881 | -0.65% | 1,516 | 1.20 | Village |
| Hopedale township | 20 | 1,797 | 1,836 | -0.22% | 51 | 35.17 | Township |
| Spring Lake township | 21 | 1,645 | 1,671 | -0.12% | 26 | 62.46 | Township |
| Heritage Lake | 22 | 1,614 | 1,664 | 0.37% | 1,425 | 1.13 | CDP |
| Delavan | 23 | 1,520 | 1,572 | -0.65% | 1,054 | 1.44 | City |
| Little Mackinaw township | 24 | 1,426 | 1,453 | -0.07% | 39 | 36.35 | Township |
| North Pekin | 25 | 1,416 | 1,473 | -0.77% | 1,031 | 1.37 | Village |
| Deer Creek township | 26 | 1,388 | 1,407 | -0.07% | 51 | 27.48 | Township |
| Sand Prairie township | 27 | 1,253 | 1,281 | -0.16% | 35 | 35.43 | Township |
| Minier | 28 | 1,121 | 1,155 | -0.62% | 1,950 | 0.57 | Village |
| South Pekin | 29 | 952 | 987 | -0.73% | 1,849 | 0.52 | Village |
| Dillon township | 30 | 929 | 947 | -0.21% | 26 | 35.95 | Township |
| Hopedale | 31 | 794 | 821 | -0.63% | 893 | 0.89 | Village |
| Deer Creek | 32 | 640 | 662 | -0.62% | 1,196 | 0.54 | Village |
| Green Valley | 33 | 602 | 627 | -0.82% | 2,000 | 0.30 | Village |
| Groveland township | 34 | 560 | 565 | 0% | 15 | 36.77 | Township |
| Hittle township | 35 | 536 | 555 | -0.74% | 18 | 30.25 | Township |
| Spring Bay | 36 | 485 | 467 | 0.83% | 705 | 0.69 | Village |
| Bay View Gardens | 37 | 348 | 355 | -0.29% | 612 | 0.57 | Village |
| Washington township | 38 | 332 | 334 | 0% | 9 | 35.58 | Township |
| Armington | 39 | 298 | 310 | -0.67% | 1,046 | 0.28 | Village |
| Boynton township | 40 | 225 | 228 | 0% | 8 | 29.59 | Township |
| Malone township | 41 | 205 | 209 | 0% | 7 | 29.68 | Township |
Pekin is the largest city in Tazewell County, with a population of 30,756.
Malone township is the smallest city in Tazewell County.
There are 41 cities in Tazewell County, Illinois.