Source: Illinois Department of Public Health, Illinois Center for Health
Statistics;
and U.S. Bureau of the Census
| County | July 1, 2010 Estimates | July 1, 2011 Estimates | July 1, 2012 Estimates |
| Illinois | 12,842,030 | 12,869,360 | 12,875,280 |
| Adams | 67,140 | 67,270 | 67,360 |
| Alexander | 8,230 | 8,050 | 7,740 |
| Bond | 17,780 | 17,800 | 17,570 |
| Boone | 54,180 | 54,320 | 54,070 |
| Brown | 6,920 | 6,900 | 6,950 |
| Bureau | 34,920 | 34,620 | 34,210 |
| Calhoun | 5,090 | 5,040 | 4,990 |
| Carroll | 15,360 | 15,260 | 14,820 |
| Cass | 13,630 | 13,630 | 13,350 |
| Champaign | 201,370 | 201,860 | 202,920 |
| Christian | 34,800 | 34,820 | 34,480 |
| Clark | 16,300 | 16,270 | 16,280 |
| Clay | 13,810 | 13,770 | 13,770 |
| Clinton | 37,840 | 38,010 | 37,890 |
| Coles | 53,950 | 53,810 | 53,560 |
| Cook | 5,199,970 | 5,220,620 | 5,228,250 |
| Crawford | 19,830 | 19,890 | 19,760 |
| Cumberland | 11,050 | 11,240 | 11,080 |
| DeKalb | 105,190 | 104,630 | 104,700 |
| DeWitt | 16,580 | 16,570 | 16,510 |
| Douglas | 19,980 | 19,880 | 19,840 |
| DuPage | 917,940 | 923,790 | 928,500 |
| Edgar | 18,530 | 18,450 | 18,300 |
| Edwards | 6,730 | 6,670 | 6,680 |
| Effingham | 34,230 | 34,310 | 34,330 |
| Fayette | 22,140 | 22,190 | 22,040 |
| Ford | 14,070 | 13,970 | 13,970 |
| Franklin | 39,570 | 39,690 | 39,450 |
| Fulton | 37,060 | 36,980 | 36,680 |
| Gallatin | 5,590 | 5,530 | 5,440 |
| Greene | 13,880 | 13,870 | 13,600 |
| Grundy | 50,130 | 50,130 | 50,310 |
| Hamilton | 8,460 | 8,450 | 8,350 |
| Hancock | 19,110 | 18,970 | 18,700 |
| Hardin | 4,310 | 4,310 | 4,270 |
| Henderson | 7,330 | 7,210 | 7,020 |
| Henry | 50,440 | 50,300 | 49,980 |
| Iroquois | 29,660 | 29,540 | 29,230 |
| Jackson | 60,360 | 60,370 | 59,920 |
| Jasper | 9,700 | 9,760 | 9,650 |
| Jefferson | 38,790 | 38,790 | 38,730 |
| Jersey | 22,960 | 22,860 | 22,690 |
| Jo Daviess | 22,680 | 22,590 | 22,360 |
| Johnson | 12,610 | 12,690 | 12,980 |
| Kane | 516,380 | 519,640 | 522,010 |
| Kankakee | 113,510 | 113,550 | 113,260 |
| Kendall | 115,240 | 116,680 | 118,330 |
| Knox | 52,940 | 52,830 | 52,250 |
| Lake | 704,490 | 702,390 | 703,210 |
| LaSalle | 113,840 | 113,600 | 113,370 |
| Lawrence | 16,830 | 16,860 | 16,940 |
| Lee | 35,940 | 35,590 | 35,360 |
| Livingston | 38,880 | 38,500 | 39,080 |
| Logan | 30,270 | 30,180 | 29,950 |
| McDonough | 32,610 | 32,520 | 32,460 |
| McHenry | 309,230 | 308,640 | 308,840 |
| McLean | 169,840 | 170,700 | 172,450 |
| Macon | 110,760 | 110,680 | 110,180 |
| Macoupin | 47,790 | 47,810 | 47,160 |
| Madison | 269,310 | 268,730 | 268,170 |
| Marion | 39,440 | 39,310 | 39,090 |
| Marshall | 12,630 | 12,520 | 12,290 |
| Mason | 14,630 | 14,510 | 14,370 |
| Massac | 15,440 | 15,350 | 15,170 |
| Menard | 12,710 | 12,710 | 12,730 |
| Mercer | 16,440 | 16,340 | 16,160 |
| Monroe | 33,010 | 33,220 | 33,270 |
| Montgomery | 30,090 | 29,930 | 29,560 |
| Morgan | 35,520 | 35,460 | 34,650 |
| Moultrie | 14,850 | 14,920 | 14,910 |
| Ogle | 53,450 | 53,110 | 52,710 |
| Peoria | 186,280 | 186,920 | 187,360 |
| Perry | 22,350 | 22,300 | 22,180 |
| Piatt | 16,720 | 16,670 | 16,480 |
| Pike | 16,420 | 16,410 | 16,340 |
| Pope | 4,460 | 4,420 | 4,230 |
| Pulaski | 6,160 | 6,060 | 5,990 |
| Putnam | 6,010 | 5,980 | 5,900 |
| Randolph | 33,450 | 33,350 | 33,030 |
| Richland | 16,230 | 16,240 | 16,130 |
| Rock Island | 147,600 | 147,170 | 146,740 |
| St. Clair | 270,400 | 270,400 | 269,170 |
| Saline | 24,940 | 25,030 | 25,000 |
| Sangamon | 197,820 | 199,120 | 199,430 |
| Schuyler | 7,540 | 7,500 | 7,430 |
| Scott | 5,350 | 5,260 | 5,270 |
| Shelby | 22,340 | 22,280 | 22,170 |
| Stark | 5,940 | 5,840 | 6,050 |
| Stephenson | 47,700 | 47,420 | 46,860 |
| Tazewell | 135,440 | 136,040 | 136,070 |
| Union | 17,770 | 17,740 | 17,640 |
| Vermilion | 81,590 | 81,620 | 80,890 |
| Wabash | 11,940 | 11,830 | 11,710 |
| Warren | 17,700 | 17,840 | 17,750 |
| Washington | 14,700 | 14,570 | 14,550 |
| Wayne | 16,750 | 16,690 | 16,580 |
| White | 14,640 | 14,670 | 14,610 |
| Whiteside | 58,450 | 58,220 | 57,550 |
| Will | 678,870 | 680,580 | 683,390 |
| Williamson | 66,400 | 66,590 | 66,680 |
| Winnebago | 295,140 | 293,780 | 292,110 |
| Woodford | 38,660 | 38,860 | 38,780 |
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Illinois Department
of Public Health 535 West Jefferson Street Springfield, Illinois 62761 Phone 217-782-4977 Fax 217-782-3987 TTY 800-547-0466 Questions or Comments |