| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Chicago | 1 | 2,727,758 | 2,741,640 | -0.14% | 11,977 | 228 | City |
| Cicero | 2 | 81,153 | 84,944 | -0.86% | 13,837 | 6 | Town |
| Schaumburg | 3 | 76,918 | 78,444 | -0.43% | 3,976 | 19 | Village |
| Evanston | 4 | 76,028 | 77,838 | -0.46% | 9,773 | 8 | City |
| Arlington Heights | 5 | 75,772 | 77,413 | -0.58% | 4,561 | 17 | Village |
| Skokie | 6 | 66,099 | 67,692 | -0.67% | 6,568 | 10 | Village |
| Palatine | 7 | 65,411 | 67,663 | -0.65% | 4,634 | 14 | Village |
| Des Plaines | 8 | 58,378 | 60,442 | -0.67% | 4,100 | 14 | City |
| Orland Park | 9 | 57,819 | 58,525 | -0.23% | 2,625 | 22 | Village |
| Oak Lawn | 10 | 56,057 | 58,124 | -0.7% | 6,540 | 9 | Village |
| Mount Prospect | 11 | 55,092 | 56,699 | -0.55% | 5,140 | 11 | Village |
| Tinley Park | 12 | 54,896 | 55,835 | -0.44% | 3,396 | 16 | Village |
| Berwyn | 13 | 54,539 | 57,006 | -0.84% | 13,970 | 4 | City |
| Oak Park | 14 | 52,421 | 54,586 | -0.76% | 11,153 | 5 | Village |
| Hoffman Estates | 15 | 50,497 | 52,374 | -0.71% | 2,459 | 21 | Village |
| Glenview | 16 | 47,484 | 48,476 | -0.48% | 3,282 | 14 | Village |
| Park Ridge | 17 | 38,210 | 39,512 | -0.66% | 5,391 | 7 | City |
| Wheeling | 18 | 38,166 | 39,228 | -0.59% | 4,401 | 9 | Village |
| Streamwood | 19 | 38,003 | 39,434 | -0.72% | 4,867 | 8 | Village |
| Hanover Park | 20 | 36,390 | 37,338 | -0.49% | 5,666 | 6 | Village |
| Northbrook | 21 | 34,597 | 35,159 | -0.42% | 2,612 | 13 | Village |
| Calumet City | 22 | 34,537 | 35,910 | -0.75% | 4,797 | 7 | City |
| Elk Grove Village | 23 | 31,659 | 32,845 | -0.71% | 2,687 | 12 | Village |
| Niles | 24 | 30,232 | 30,813 | -0.69% | 5,170 | 6 | Village |
| Burbank | 25 | 28,394 | 29,346 | -0.64% | 6,809 | 4 | City |
| Lansing | 26 | 27,857 | 28,963 | -0.75% | 3,733 | 7 | Village |
| Wilmette | 27 | 27,305 | 28,079 | -0.56% | 5,056 | 5 | Village |
| Oak Forest | 28 | 26,656 | 27,378 | -0.51% | 4,424 | 6 | City |
| Chicago Heights | 29 | 26,305 | 27,377 | -0.77% | 2,558 | 10 | City |
| Morton Grove | 30 | 24,402 | 25,207 | -0.73% | 4,796 | 5 | Village |
| Melrose Park | 31 | 23,762 | 24,660 | -0.73% | 5,459 | 4 | Village |
| Rolling Meadows | 32 | 23,581 | 24,164 | -0.46% | 4,199 | 6 | City |
| Elmwood Park | 33 | 23,500 | 24,429 | -0.74% | 12,317 | 2 | Village |
| Maywood | 34 | 23,315 | 23,420 | -0.06% | 8,581 | 3 | Village |
| Blue Island | 35 | 21,647 | 22,473 | -0.72% | 5,317 | 4 | City |
| Park Forest | 36 | 20,935 | 21,605 | -0.68% | 4,220 | 5 | Village |
| South Holland | 37 | 20,599 | 21,387 | -0.72% | 2,847 | 7 | Village |
| Dolton | 38 | 20,517 | 21,327 | -0.75% | 4,489 | 5 | Village |
| Harvey | 39 | 19,736 | 20,247 | -0.57% | 3,180 | 6 | City |
| Evergreen Park | 40 | 19,147 | 19,866 | -0.71% | 6,053 | 3 | Village |
| Brookfield | 41 | 18,743 | 19,446 | -0.72% | 6,117 | 3 | Village |
| Homewood | 42 | 18,632 | 19,378 | -0.75% | 3,721 | 5 | Village |
| Lemont | 43 | 18,614 | 17,803 | 0.55% | 2,037 | 9 | Village |
| Matteson | 44 | 18,429 | 19,020 | -0.61% | 1,984 | 9 | Village |
| Alsip | 45 | 18,357 | 19,008 | -0.68% | 2,812 | 7 | Village |
| Franklin Park | 46 | 17,981 | 18,342 | -0.35% | 3,764 | 5 | Village |
| Bellwood | 47 | 17,974 | 18,721 | -0.78% | 7,495 | 2 | Village |
| Palos Hills | 48 | 17,920 | 18,461 | -0.6% | 4,220 | 4 | City |
| Bridgeview | 49 | 16,415 | 16,962 | -0.64% | 3,972 | 4 | Village |
| Westchester | 50 | 16,176 | 16,830 | -0.76% | 4,388 | 4 | Village |
| Country Club Hills | 51 | 16,097 | 16,712 | -0.73% | 3,239 | 5 | City |
| La Grange | 52 | 15,848 | 16,297 | -0.55% | 6,276 | 3 | Village |
| Prospect Heights | 53 | 15,447 | 15,990 | -0.68% | 3,672 | 4 | City |
| Norridge | 54 | 14,716 | 15,205 | -0.62% | 8,139 | 2 | Village |
| Hickory Hills | 55 | 14,016 | 14,455 | -0.6% | 4,928 | 3 | City |
| Chicago Ridge | 56 | 13,949 | 14,407 | -0.62% | 6,150 | 2 | Village |
| Midlothian | 57 | 13,745 | 14,248 | -0.69% | 4,876 | 3 | Village |
| Forest Park | 58 | 13,720 | 14,279 | -0.79% | 5,712 | 2 | Village |
| Western Springs | 59 | 13,574 | 13,591 | -0.1% | 4,874 | 3 | Village |
| La Grange Park | 60 | 13,397 | 13,699 | -0.42% | 6,000 | 2 | Village |
| Lincolnwood | 61 | 12,952 | 13,413 | -0.67% | 4,811 | 3 | Village |
| Hazel Crest | 62 | 12,928 | 13,427 | -0.74% | 3,584 | 4 | Village |
| Winnetka | 63 | 12,467 | 12,704 | -0.41% | 3,271 | 4 | Village |
| Richton Park | 64 | 12,424 | 12,737 | -0.47% | 2,829 | 4 | Village |
| Northlake | 65 | 12,376 | 12,829 | -0.69% | 3,897 | 3 | City |
| Justice | 66 | 12,212 | 12,568 | -0.59% | 4,300 | 3 | Village |
| Palos Heights | 67 | 12,001 | 12,421 | -0.69% | 3,180 | 4 | City |
| Schiller Park | 68 | 11,235 | 11,666 | -0.72% | 4,056 | 3 | Village |
| Markham | 69 | 11,193 | 11,619 | -0.72% | 2,071 | 5 | City |
| River Forest | 70 | 11,193 | 12,220 | -1.76% | 4,513 | 2 | Village |
| Burr Ridge | 71 | 11,177 | 11,169 | -0.02% | 1,496 | 7 | Village |
| Summit | 72 | 10,668 | 11,117 | -0.79% | 5,034 | 2 | Village |
| Worth | 73 | 10,630 | 10,931 | -0.62% | 4,487 | 2 | Village |
| Crestwood | 74 | 10,469 | 10,781 | -0.57% | 3,434 | 3 | Village |
| River Grove | 75 | 10,374 | 10,573 | -0.34% | 4,339 | 2 | Village |
| Lyons | 76 | 10,352 | 10,773 | -0.78% | 4,691 | 2 | Village |
| Riverdale | 77 | 10,200 | 10,622 | -0.78% | 2,853 | 4 | Village |
| Sauk Village | 78 | 9,560 | 9,891 | -0.67% | 2,395 | 4 | Village |
| Lynwood | 79 | 9,333 | 9,092 | 0.39% | 1,836 | 5 | Village |
| Steger | 80 | 9,302 | 9,578 | -0.53% | 2,733 | 3 | Village |
| Flossmoor | 81 | 9,290 | 9,646 | -0.73% | 2,538 | 4 | Village |
| Riverside | 82 | 8,863 | 9,268 | -0.85% | 4,481 | 2 | Village |
| Glencoe | 83 | 8,698 | 8,819 | -0.3% | 2,339 | 4 | Village |
| Harwood Heights | 84 | 8,696 | 9,031 | -0.74% | 10,541 | 1 | Village |
| Glenwood | 85 | 8,354 | 8,679 | -0.74% | 2,559 | 3 | Village |
| Hillside | 86 | 8,080 | 8,282 | -0.74% | 2,551 | 3 | Village |
| Broadview | 87 | 7,850 | 7,973 | -0.27% | 4,418 | 2 | Village |
| Inverness | 88 | 7,375 | 7,596 | -0.58% | 1,129 | 7 | Village |
| North Riverside | 89 | 7,105 | 7,397 | -0.78% | 4,322 | 2 | Village |
| Stickney | 90 | 6,852 | 7,093 | -0.65% | 3,561 | 2 | Village |
| Calumet Park | 91 | 6,721 | 6,990 | -0.75% | 6,017 | 1 | Village |
| Orland Hills | 92 | 6,614 | 6,865 | -0.74% | 5,776 | 1 | Village |
| Countryside | 93 | 6,223 | 6,408 | -0.59% | 2,162 | 3 | City |
| Willow Springs | 94 | 5,773 | 5,852 | -0.26% | 1,391 | 4 | Village |
| Northfield | 95 | 5,604 | 5,741 | -0.5% | 1,735 | 3 | Village |
| Posen | 96 | 5,365 | 5,575 | -0.74% | 4,589 | 1 | Village |
| Lake Barrington | 97 | 5,142 | 5,090 | 0.23% | 896 | 6 | Village |
| Berkeley | 98 | 5,099 | 5,319 | -0.82% | 3,637 | 1 | Village |
| South Barrington | 99 | 5,069 | 5,066 | -0.04% | 680 | 7 | Village |
| Palos Park | 100 | 4,789 | 4,872 | -0.33% | 779 | 6 | Village |
| Robbins | 101 | 4,576 | 4,623 | -0.26% | 3,158 | 1 | Village |
| Olympia Fields | 102 | 4,564 | 4,713 | -0.63% | 1,553 | 3 | Village |
| Stone Park | 103 | 4,455 | 4,568 | -0.49% | 12,951 | 0 | Village |
| Hometown | 104 | 4,158 | 4,332 | -0.79% | 8,681 | 0 | City |
| Barrington Hills | 105 | 4,081 | 4,100 | -0.12% | 151 | 27 | Village |
| Indian Head Park | 106 | 3,936 | 4,066 | -0.63% | 4,223 | 1 | Village |
| Burnham | 107 | 3,892 | 4,033 | -0.69% | 2,098 | 2 | Village |
| South Chicago Heights | 108 | 3,856 | 3,999 | -0.72% | 2,439 | 2 | Village |
| Rosemont | 109 | 3,785 | 3,939 | -0.79% | 2,112 | 2 | Village |
| Riverwoods | 110 | 3,762 | 3,787 | -0.11% | 948 | 4 | Village |
| Deer Park | 111 | 3,639 | 3,680 | -0.22% | 992 | 4 | Village |
| North Barrington | 112 | 3,122 | 3,133 | -0.1% | 661 | 5 | Village |
| East Dundee | 113 | 3,119 | 3,193 | -0.35% | 1,065 | 3 | Village |
| Dixmoor | 114 | 2,936 | 3,008 | -0.51% | 2,351 | 1 | Village |
| Oakbrook Terrace | 115 | 2,785 | 2,820 | -0.25% | 2,129 | 1 | City |
| Kenilworth | 116 | 2,420 | 2,507 | -0.7% | 3,987 | 1 | Village |
| Thornton | 117 | 2,280 | 2,379 | -0.83% | 960 | 2 | Village |
| Merrionette Park | 118 | 1,903 | 1,963 | -0.63% | 5,075 | 0 | Village |
| Ford Heights | 119 | 1,738 | 1,807 | -0.74% | 893 | 2 | Village |
| Phoenix | 120 | 1,633 | 1,702 | -0.79% | 3,519 | 0 | Village |
| Port Barrington | 121 | 1,582 | 1,586 | -0.13% | 1,364 | 1 | Village |
| Hodgkins | 122 | 1,475 | 1,496 | -0.34% | 544 | 3 | Village |
| Bannockburn | 123 | 1,287 | 1,391 | -1.61% | 635 | 2 | Village |
| East Hazel Crest | 124 | 1,240 | 1,289 | -0.8% | 1,582 | 1 | Village |
| Tower Lakes | 125 | 1,196 | 1,222 | -0.42% | 1,301 | 1 | Village |
| Forest View | 126 | 757 | 787 | -0.79% | 648 | 1 | Village |
| Bedford Park | 127 | 588 | 588 | -0.17% | 99 | 6 | Village |
| Golf | 128 | 508 | 510 | -0.2% | 1,134 | 0 | Village |
| McCook | 129 | 238 | 248 | -0.83% | 91 | 3 | Village |
Chicago is the largest city in Cook County, with a population of 2,727,758.
McCook is the smallest city in Cook County, with a population of 238.
There are 129 cities in Cook County, Illinois.