*Data corrected April 30, 2010.
Recently released population estimates from the U.S. Census Bureau show that Christian County had the largest population change between 2000 and 2009 at 42.7 percent, followed by Lincoln County (36.9 percent) and Warren County (28.4 percent). St. Louis County had the largest population in 2009 with 992,408, representing 16.6 percent of the state's total estimated population. Jackson County is Missouri's second largest with an estimated population of 705,708.
See 2009 County Population Estimates map.
See 2000-2009 County Percent Change in Population Estimates map.
See 2008-2009 County Percent Change in Population Estimates map.
| 2009 Population Estimates | |||||||
| Geographic Area | 2000 Census | July 1, 2008 | July 1, 2009 | % Chng 2000 to 2009 | Chg 2000 to 2009 | % Chg 2008 to 2009 | Chg 2008 to 2009 |
| Missouri | 5,595,211 | 5,956,335 | 5,987,580 | 7.01% | 392,369 | 0.52% | 31,245 |
| Adair County | 24,977 | 24,998 | 25,135 | 0.63% | 158 | 0.55% | 137 |
| Andrew County | 16,492 | 16,914 | 17,052 | 3.40% | 560 | 0.82% | 138 |
| Atchison County | 6,430 | 6,015 | 6,036 | -6.13% | -394 | 0.35% | 21 |
| Audrain County | 25,853 | 25,777 | 25,556 | -1.15% | -297 | -0.86% | -221 |
| Barry County | 34,010 | 36,209 | 35,881 | 5.50% | 1,871 | -0.91% | -328 |
| Barton County | 12,541 | 12,521 | 12,386 | -1.24% | -155 | -1.08% | -135 |
| Bates County | 16,653 | 16,918 | 16,761 | 0.65% | 108 | -0.93% | -157 |
| Benton County | 17,180 | 18,534 | 18,461 | 7.46% | 1,281 | -0.39% | -73 |
| Bollinger County | 12,029 | 11,958 | 11,841 | -1.56% | -188 | -0.98% | -117 |
| Boone County | 135,454 | 154,331 | 156,377 | 15.45% | 20,923 | 1.33% | 2,046 |
| Buchanan County | 85,998 | 89,186 | 89,856 | 4.49% | 3,858 | 0.75% | 670 |
| Butler County | 40,867 | 41,247 | 41,471 | 1.48% | 604 | 0.54% | 224 |
| Caldwell County | 8,969 | 9,189 | 9,160 | 2.13% | 191 | -0.32% | -29 |
| Callaway County | 40,766 | 43,588 | 43,727 | 7.26% | 2,961 | 0.32% | 139 |
| Camden County | 37,051 | 40,711 | 40,705 | 9.86% | 3,654 | -0.01% | -6 |
| Cape Girardeau County | 68,693 | 73,217 | 73,957 | 7.66% | 5,264 | 1.01% | 740 |
| Carroll County | 10,285 | 9,705 | 9,535 | -7.29% | -750 | -1.75% | -170 |
| Carter County | 5,941 | 5,913 | 5,870 | -1.20% | -71 | -0.73% | -43 |
| Cass County | 82,092 | 99,281 | 100,184 | 22.04% | 18,092 | 0.91% | 903 |
| Cedar County | 13,733 | 13,700 | 13,544 | -1.38% | -189 | -1.14% | -156 |
| Chariton County | 8,438 | 7,671 | 7,594 | -10.00% | -844 | -1.00% | -77 |
| Christian County | 54,285 | 75,646 | 77,455 | 42.68% | 23,170 | 2.39% | 1,809 |
| Clark County | 7,416 | 7,160 | 7,127 | -3.90% | -289 | -0.46% | -33 |
| Clay County | 184,006 | 223,370 | 228,358 | 24.10% | 44,352 | 2.23% | 4,988 |
| Clinton County | 18,979 | 21,022 | 21,002 | 10.66% | 2,023 | -0.10% | -20 |
| Cole County | 71,397 | 74,388 | 75,018 | 5.07% | 3,621 | 0.85% | 630 |
| Cooper County | 16,670 | 17,326 | 17,298 | 3.77% | 628 | -0.16% | -28 |
| Crawford County | 22,804 | 23,877 | 23,915 | 4.87% | 1,111 | 0.16% | 38 |
| Dade County | 7,923 | 7,465 | 7,316 | -7.66% | -607 | -2.00% | -149 |
| Dallas County | 15,661 | 16,799 | 16,637 | 6.23% | 976 | -0.96% | -162 |
| Daviess County | 8,016 | 8,041 | 8,078 | 0.77% | 62 | 0.46% | 37 |
| DeKalb County | 11,597 | 12,181 | 12,112 | 4.44% | 515 | -0.57% | -69 |
| Dent County | 14,927 | 15,079 | 15,042 | 0.77% | 115 | -0.25% | -37 |
| Douglas County | 13,084 | 13,584 | 13,608 | 4.00% | 524 | 0.18% | 24 |
| Dunklin County | 33,155 | 31,326 | 31,039 | -6.38% | -2,116 | -0.92% | -287 |
| Franklin County | 93,807 | 100,867 | 101,263 | 7.95% | 7,456 | 0.39% | 396 |
| Gasconade County | 15,342 | 15,253 | 15,096 | -1.60% | -246 | -1.03% | -157 |
| Gentry County | 6,861 | 6,205 | 6,108 | -10.98% | -753 | -1.56% | -97 |
| Greene County | 240,391 | 266,898 | 269,630 | 12.16% | 29,239 | 1.02% | 2,732 |
| Grundy County | 10,432 | 10,083 | 10,047 | -3.69% | -385 | -0.36% | -36 |
| Harrison County | 8,850 | 8,738 | 8,769 | -0.92% | -81 | 0.35% | 31 |
| Henry County | 21,997 | 22,171 | 22,176 | 0.81% | 179 | 0.02% | 5 |
| Hickory County | 8,940 | 8,992 | 8,903 | -0.41% | -37 | -0.99% | -89 |
| Holt County | 5,351 | 4,895 | 4,868 | -9.03% | -483 | -0.55% | -27 |
| Howard County | 10,212 | 9,851 | 9,857 | -3.48% | -355 | 0.06% | 6 |
| Howell County | 37,238 | 38,968 | 38,921 | 4.52% | 1,683 | -0.12% | -47 |
| Iron County | 10,697 | 9,995 | 9,943 | -7.05% | -754 | -0.52% | -52 |
| Jackson County | 654,880 | 700,699 | 705,708 | 7.76% | 50,828 | 0.71% | 5,009 |
| Jasper County | 104,686 | 116,634 | 118,179 | 12.89% | 13,493 | 1.32% | 1,545 |
| Jefferson County | 198,099 | 217,599 | 219,046 | 10.57% | 20,947 | 0.66% | 1,447 |
| Johnson County | 48,258 | 52,161 | 52,657 | 9.12% | 4,399 | 0.95% | 496 |
| Knox County | 4,361 | 4,005 | 3,981 | -8.71% | -380 | -0.60% | -24 |
| Laclede County | 32,513 | 35,478 | 35,432 | 8.98% | 2,919 | -0.13% | -46 |
| Lafayette County | 32,960 | 32,824 | 32,572 | -1.18% | -388 | -0.77% | -252 |
| Lawrence County | 35,204 | 37,638 | 37,648 | 6.94% | 2,444 | 0.03% | 10 |
| Lewis County | 10,494 | 9,887 | 9,791 | -6.70% | -703 | -0.97% | -96 |
| Lincoln County | 38,944 | 52,726 | 53,311 | 36.89% | 14,367 | 1.11% | 585 |
| Linn County | 13,754 | 12,655 | 12,606 | -8.35% | -1,148 | -0.39% | -49 |
| Livingston County | 14,558 | 14,123 | 14,235 | -2.22% | -323 | 0.79% | 112 |
| McDonald County | 21,681 | 22,873 | 23,063 | 6.37% | 1,382 | 0.83% | 190 |
| Macon County | 15,762 | 15,434 | 15,359 | -2.56% | -403 | -0.49% | -75 |
| Madison County | 11,800 | 12,400 | 12,341 | 4.58% | 541 | -0.48% | -59 |
| Maries County | 8,903 | 8,924 | 8,821 | -0.92% | -82 | -1.15% | -103 |
| Marion County | 28,289 | 28,283 | 28,449 | 0.57% | 160 | 0.59% | 166 |
| Mercer County | 3,757 | 3,474 | 3,475 | -7.51% | -282 | 0.03% | 1 |
| Miller County | 23,564 | 24,817 | 24,778 | 5.15% | 1,214 | -0.16% | -39 |
| Mississippi County | 13,427 | 13,378 | 13,266 | -1.20% | -161 | -0.84% | -112 |
| Moniteau County | 14,827 | 15,075 | 15,132 | 2.06% | 305 | 0.38% | 57 |
| Monroe County | 9,311 | 9,138 | 8,993 | -3.42% | -318 | -1.59% | -145 |
| Montgomery County | 12,136 | 11,858 | 11,698 | -3.61% | -438 | -1.35% | -160 |
| Morgan County | 19,309 | 20,780 | 20,527 | 6.31% | 1,218 | -1.22% | -253 |
| New Madrid County | 19,760 | 17,537 | 17,480 | -11.54% | -2,280 | -0.33% | -57 |
| Newton County | 52,636 | 55,981 | 56,121 | 6.62% | 3,485 | 0.25% | 140 |
| Nodaway County | 21,912 | 22,041 | 22,130 | 0.99% | 218 | 0.40% | 89 |
| Oregon County | 10,344 | 10,324 | 10,291 | -0.51% | -53 | -0.32% | -33 |
| Osage County | 13,062 | 13,414 | 13,561 | 3.82% | 499 | 1.10% | 147 |
| Ozark County | 9,542 | 9,386 | 9,315 | -2.38% | -227 | -0.76% | -71 |
| Pemiscot County | 20,047 | 18,338 | 18,193 | -9.25% | -1,854 | -0.79% | -145 |
| Perry County | 18,132 | 18,707 | 18,847 | 3.94% | 715 | 0.75% | 140 |
| Pettis County | 39,403 | 41,065 | 41,421 | 5.12% | 2,018 | 0.87% | 356 |
| Phelps County | 39,825 | 42,132 | 42,248 | 6.08% | 2,423 | 0.28% | 116 |
| Pike County | 18,351 | 18,498 | 18,406 | 0.30% | 55 | -0.50% | -92 |
| Platte County | 73,781 | 89,303 | 90,688 | 22.92% | 16,907 | 1.55% | 1,385 |
| Polk County | 26,992 | 30,343 | 30,626 | 13.46% | 3,634 | 0.93% | 283 |
| Pulaski County | 41,165 | 44,760 | 46,457 | 12.86% | 5,292 | 3.79% | 1,697 |
| Putnam County | 5,223 | 4,838 | 4,759 | -8.88% | -464 | -1.63% | -79 |
| Ralls County | 9,626 | 9,670 | 9,634 | 0.08% | 8 | -0.37% | -36 |
| Randolph County | 24,663 | 25,641 | 25,501 | 3.40% | 838 | -0.55% | -140 |
| Ray County | 23,354 | 23,531 | 23,358 | 0.02% | 4 | -0.74% | -173 |
| Reynolds County | 6,689 | 6,315 | 6,202 | -7.28% | -487 | -1.79% | -113 |
| Ripley County | 13,509 | 13,477 | 13,395 | -0.84% | -114 | -0.61% | -82 |
| St. Charles County | 283,883 | 349,595 | 355,367 | 25.18% | 71,484 | 1.65% | 5,772 |
| St. Clair County | 9,652 | 9,360 | 9,276 | -3.90% | -376 | -0.90% | -84 |
| Ste. Genevieve County | 17,842 | 17,699 | 17,542 | -1.68% | -300 | -0.89% | -157 |
| St. Francois County | 55,641 | 63,314 | 63,884 | 14.81% | 8,243 | 0.90% | 570 |
| St. Louis County | 1,016,315 | 992,331 | 992,408 | -2.35% | -23,907 | 0.01% | 77 |
| Saline County | 23,756 | 22,595 | 22,821 | -3.94% | -935 | 1.00% | 226 |
| Schuyler County | 4,170 | 4,123 | 4,144 | -0.62% | -26 | 0.51% | 21 |
| Scotland County | 4,983 | 4,788 | 4,803 | -3.61% | -180 | 0.31% | 15 |
| Scott County | 40,422 | 40,764 | 40,855 | 1.07% | 433 | 0.22% | 91 |
| Shannon County | 8,324 | 8,350 | 8,361 | 0.44% | 37 | 0.13% | 11 |
| Shelby County | 6,799 | 6,376 | 6,325 | -6.97% | -474 | -0.80% | -51 |
| Stoddard County | 29,705 | 29,387 | 29,069 | -2.14% | -636 | -1.08% | -318 |
| Stone County | 28,658 | 31,495 | 31,424 | 9.65% | 2,766 | -0.23% | -71 |
| Sullivan County | 7,219 | 6,831 | 6,835 | -5.32% | -384 | 0.06% | 4 |
| Taney County | 39,703 | 47,274 | 48,023 | 20.96% | 8,320 | 1.58% | 749 |
| Texas County | 23,003 | 24,497 | 24,563 | 6.78% | 1,560 | 0.27% | 66 |
| Vernon County | 20,454 | 20,099 | 20,166 | -1.41% | -288 | 0.33% | 67 |
| Warren County | 24,525 | 31,153 | 31,485 | 28.38% | 6,960 | 1.07% | 332 |
| Washington County | 23,344 | 24,488 | 24,400 | 4.52% | 1,056 | -0.36% | -88 |
| Wayne County | 13,259 | 12,454 | 12,392 | -6.54% | -867 | -0.50% | -62 |
| Webster County | 31,045 | 36,439 | 36,552 | 17.74% | 5,507 | 0.31% | 113 |
| Worth County | 2,382 | 2,011 | 2,014 | -15.45% | -368 | 0.15% | 3 |
| Wright County | 17,955 | 18,255 | 17,908 | -0.26% | -47 | -1.90% | -347 |
| St. Louis city | 348,189 | 356,730 | 356,587 | 2.41% | 8,398 | -0.04% | -143 |
