| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| St. Louis | 1 | 273,179 | 300,302 | -1.79% | 4,426 | 62 | City |
| Florissant | 2 | 50,820 | 52,447 | -0.59% | 4,049 | 13 | City |
| Chesterfield | 3 | 49,165 | 49,946 | -0.29% | 1,546 | 32 | City |
| University City | 4 | 34,444 | 35,165 | -0.61% | 5,856 | 6 | City |
| Ballwin | 5 | 30,733 | 31,662 | -0.54% | 3,422 | 9 | City |
| Kirkwood | 6 | 29,296 | 29,453 | -0.12% | 3,191 | 9 | City |
| Maryland Heights | 7 | 27,403 | 28,254 | -0.57% | 1,252 | 22 | City |
| Hazelwood | 8 | 24,727 | 25,409 | -0.49% | 1,542 | 16 | City |
| Webster Groves | 9 | 23,328 | 23,996 | -0.52% | 3,945 | 6 | City |
| Creve Coeur | 10 | 18,404 | 18,811 | -0.41% | 1,791 | 10 | City |
| Manchester | 11 | 18,013 | 18,321 | -0.31% | 3,580 | 5 | City |
| Clayton | 12 | 17,842 | 17,361 | 0.2% | 7,117 | 3 | City |
| Ferguson | 13 | 17,837 | 18,480 | -0.65% | 2,891 | 6 | City |
| Overland | 14 | 15,378 | 15,913 | -0.62% | 3,504 | 4 | City |
| Eureka | 15 | 13,787 | 11,777 | 2.72% | 1,238 | 11 | City |
| Jennings | 16 | 13,120 | 12,901 | 0.21% | 3,515 | 4 | City |
| St. Ann | 17 | 12,539 | 12,974 | -0.62% | 3,974 | 3 | City |
| Crestwood | 18 | 12,165 | 12,395 | -0.34% | 3,392 | 4 | City |
| Town and Country | 19 | 11,612 | 11,631 | -0.06% | 1,011 | 11 | City |
| Bridgeton | 20 | 11,240 | 11,451 | -0.33% | 772 | 15 | City |
| Bellefontaine Neighbors | 21 | 10,293 | 10,700 | -0.72% | 2,339 | 4 | City |
| Des Peres | 22 | 9,096 | 9,129 | -0.07% | 2,106 | 4 | City |
| Sunset Hills | 23 | 9,050 | 9,183 | -0.28% | 1,008 | 9 | City |
| Richmond Heights | 24 | 9,047 | 9,295 | -0.51% | 3,949 | 2 | City |
| Olivette | 25 | 9,046 | 8,516 | 1.22% | 3,265 | 3 | City |
| Ladue | 26 | 8,920 | 8,980 | -0.16% | 1,042 | 9 | City |
| Brentwood | 27 | 8,049 | 8,219 | -0.37% | 4,121 | 2 | City |
| Berkeley | 28 | 7,983 | 8,222 | -0.54% | 1,609 | 5 | City |
| Maplewood | 29 | 7,980 | 8,275 | -0.66% | 5,099 | 2 | City |
| Valley Park | 30 | 6,732 | 6,926 | -0.52% | 1,495 | 5 | City |
| Black Jack | 31 | 6,526 | 6,639 | -0.32% | 2,524 | 3 | City |
| St. John | 32 | 6,399 | 6,631 | -0.65% | 4,494 | 1 | City |
| Shrewsbury | 33 | 6,194 | 6,397 | -0.59% | 4,298 | 1 | City |
| Glendale | 34 | 6,035 | 6,174 | -0.41% | 4,653 | 1 | City |
| Dellwood | 35 | 4,808 | 4,900 | -0.35% | 4,636 | 1 | City |
| Rock Hill | 36 | 4,652 | 4,740 | -0.34% | 4,218 | 1 | City |
| Normandy | 37 | 4,371 | 4,397 | -0.21% | 2,359 | 2 | City |
| Breckenridge Hills | 38 | 4,328 | 4,447 | -0.51% | 5,403 | 1 | City |
| Fenton | 39 | 4,047 | 4,113 | -0.32% | 645 | 6 | City |
| Woodson Terrace | 40 | 3,888 | 3,964 | -0.36% | 5,017 | 1 | City |
| Frontenac | 41 | 3,828 | 3,624 | 1% | 1,329 | 3 | City |
| Northwoods | 42 | 3,556 | 3,683 | -0.64% | 5,095 | 1 | City |
| Pine Lawn | 43 | 2,665 | 2,759 | -0.63% | 4,305 | 1 | City |
| Green Park | 44 | 2,662 | 2,706 | -0.3% | 2,034 | 1 | City |
| Pagedale | 45 | 2,500 | 2,562 | -0.44% | 2,076 | 1 | City |
| Riverview | 46 | 2,315 | 2,396 | -0.64% | 2,789 | 1 | Village |
| Marlborough | 47 | 2,177 | 2,217 | -0.37% | 9,590 | 0 | Village |
| Moline Acres | 48 | 2,079 | 2,152 | -0.67% | 3,628 | 1 | City |
| Bel-Ridge | 49 | 2,056 | 2,133 | -0.68% | 2,660 | 1 | Village |
| Warson Woods | 50 | 1,982 | 2,020 | -0.4% | 3,489 | 1 | City |
| Hanley Hills | 51 | 1,956 | 1,993 | -0.36% | 5,448 | 0 | Village |
| Vinita Park | 52 | 1,910 | 1,983 | -0.68% | 2,449 | 1 | City |
| Wellston | 53 | 1,592 | 1,535 | 0.76% | 1,708 | 1 | City |
| Lakeshire | 54 | 1,500 | 1,555 | -0.66% | 6,696 | 0 | City |
| Winchester | 55 | 1,391 | 1,439 | -0.64% | 5,542 | 0 | City |
| Oakland | 56 | 1,367 | 1,389 | -0.36% | 2,267 | 1 | City |
| Bel-Nor | 57 | 1,341 | 1,395 | -0.74% | 2,132 | 1 | Village |
| Velda City | 58 | 1,331 | 1,187 | 1.68% | 8,166 | 0 | City |
| Charlack | 59 | 1,269 | 1,298 | -0.47% | 4,683 | 0 | City |
| Hillsdale | 60 | 1,172 | 1,213 | -0.68% | 3,427 | 0 | Village |
| Calverton Park | 61 | 1,130 | 1,152 | -0.35% | 2,749 | 0 | City |
| Cool Valley | 62 | 998 | 1,036 | -0.7% | 2,179 | 0 | City |
| Country Club Hills | 63 | 994 | 1,015 | -0.4% | 5,344 | 0 | City |
| Grantwood Village | 64 | 921 | 940 | -0.43% | 1,127 | 1 | Town |
| Norwood Court | 65 | 874 | 888 | -0.34% | 7,164 | 0 | Town |
| Pasadena Hills | 66 | 874 | 910 | -0.79% | 4,123 | 0 | City |
| Velda Village Hills | 67 | 844 | 879 | -0.82% | 7,033 | 0 | City |
| Edmundson | 68 | 839 | 856 | -0.36% | 3,062 | 0 | City |
| Bella Villa | 69 | 717 | 745 | -0.83% | 5,602 | 0 | City |
| Flordell Hills | 70 | 697 | 725 | -0.71% | 5,667 | 0 | City |
| Greendale | 71 | 631 | 644 | -0.47% | 3,286 | 0 | City |
| Twin Oaks | 72 | 581 | 590 | -0.34% | 2,160 | 0 | Village |
| Sycamore Hills | 73 | 543 | 558 | -0.55% | 4,052 | 0 | Village |
| Crystal Lake Park | 74 | 499 | 508 | -0.4% | 5,144 | 0 | City |
| Beverly Hills | 75 | 453 | 471 | -0.66% | 5,033 | 0 | City |
| Pasadena Park | 76 | 423 | 439 | -0.7% | 4,316 | 0 | Village |
| Wilbur Park | 77 | 423 | 434 | -0.47% | 7,169 | 0 | Village |
| Huntleigh | 78 | 350 | 358 | -0.57% | 353 | 1 | City |
| Westwood | 79 | 307 | 313 | -0.32% | 488 | 1 | Village |
| Uplands Park | 80 | 303 | 312 | -0.66% | 4,591 | 0 | Village |
| Kinloch | 81 | 260 | 266 | -0.38% | 358 | 1 | City |
| Bellerive Acres | 82 | 179 | 187 | -1.1% | 526 | 0 | City |
| Country Life Acres | 83 | 70 | 73 | -1.41% | 565 | 0 | Village |
| Champ | 84 | 9 | 9 | 0% | 11 | 1 | Village |
St. Louis is the largest city in St. Louis County, with a population of 273,179.
Champ is the smallest city in St. Louis County, with a population of 9.
There are 84 cities in St. Louis County, Missouri.