(Links below lead to Quick Facts for Maryland Counties / Independent Cities: People, Business & Geography at U.S. Census Bureau.)
| Area | 7/1/2008 | 7/1/2007 | 7/1/2006 | 7/1/2005 | 7/1/2004 | 7/1/2003 | 7/1/2002 | 7/1/2001 | 7/1/2000 | Census 2000 |
| Maryland | 5,633,597 | 5,618,899 | 5,602,258 | 5,575,552 | 5,538,989 | 5,495,009 | 5,439,327 | 5,375,659 | 5,310,451 | 5,296,486 |
|---|---|---|---|---|---|---|---|---|---|---|
| Allegany County | 72,238 | 72,603 | 72,415 | 72,716 | 73,398 | 73,327 | 73,737 | 74,320 | 74,807 | 74,930 |
| Anne Arundel County | 512,790 | 510,507 | 509,037 | 509,414 | 508,132 | 505,000 | 502,267 | 496,881 | 491,331 | 489,656 |
| Baltimore city | 636,919 | 640,150 | 640,961 | 640,064 | 641,004 | 642,324 | 641,950 | 645,253 | 648,587 | 651,154 |
| Baltimore County | 785,618 | 785,830 | 785,200 | 781,452 | 778,810 | 773,921 | 768,047 | 762,269 | 755,992 | 754,292 |
| Calvert County | 88,698 | 88,145 | 87,536 | 86,738 | 85,311 | 83,342 | 80,380 | 77,333 | 75,164 | 74,563 |
| Caroline County | 33,138 | 32,797 | 32,209 | 31,489 | 30,736 | 30,634 | 30,144 | 29,891 | 29,825 | 29,772 |
| Carroll County | 169,353 | 168,786 | 168,180 | 166,820 | 165,000 | 162,229 | 158,597 | 154,451 | 151,577 | 150,897 |
| Cecil County | 99,926 | 99,368 | 98,520 | 96,626 | 94,673 | 92,367 | 90,059 | 88,256 | 86,465 | 85,951 |
| Charles County | 140,764 | 140,169 | 139,164 | 137,144 | 134,531 | 131,448 | 127,777 | 124,691 | 121,204 | 120,546 |
| Dorchester County | 31,998 | 31,845 | 31,358 | 31,116 | 30,854 | 30,465 | 30,433 | 30,602 | 30,586 | 30,674 |
| Frederick County | 225,721 | 224,147 | 221,492 | 219,178 | 216,232 | 212,735 | 208,498 | 201,942 | 196,501 | 195,277 |
| Garrett County | 29,698 | 29,641 | 29,603 | 29,660 | 29,811 | 29,919 | 29,823 | 29,726 | 29,824 | 29,846 |
| Harford County | 240,351 | 239,406 | 239,193 | 237,094 | 233,784 | 230,654 | 226,732 | 222,251 | 219,464 | 218,590 |
| Howard County | 274,995 | 272,611 | 269,631 | 267,133 | 264,915 | 262,517 | 259,129 | 255,016 | 249,520 | 247,842 |
| Kent County | 20,151 | 19,879 | 19,798 | 19,768 | 19,595 | 19,555 | 19,497 | 19,367 | 19,267 | 19,197 |
| Montgomery County | 950,680 | 941,491 | 936,070 | 930,286 | 923,094 | 917,160 | 908,233 | 894,878 | 877,495 | 873,341 |
| Prince George's County | 820,852 | 825,318 | 831,602 | 835,588 | 832,806 | 828,822 | 823,186 | 814,689 | 803,207 | 801,515 |
| Queen Anne's County | 47,091 | 46,515 | 45,820 | 45,014 | 44,527 | 43,774 | 42,584 | 41,291 | 40,767 | 40,563 |
| Somerset County | 26,119 | 26,147 | 25,775 | 25,530 | 25,613 | 25,407 | 25,374 | 25,160 | 24,721 | 24,747 |
| St. Mary's County | 101,578 | 100,262 | 98,510 | 96,885 | 94,884 | 92,606 | 89,860 | 87,451 | 86,520 | 86,211 |
| Talbot County | 36,215 | 36,132 | 36,035 | 35,603 | 35,163 | 34,539 | 34,344 | 34,098 | 33,892 | 33,812 |
| Washington County | 145,384 | 144,662 | 142,984 | 141,119 | 138,707 | 136,331 | 134,550 | 132,982 | 132,098 | 131,923 |
| Wicomico County | 94,046 | 93,218 | 92,096 | 90,330 | 88,541 | 87,252 | 85,935 | 85,271 | 84,861 | 84,644 |
| Worcester County | 49,274 | 49,270 | 49,069 | 48,785 | 48,868 | 48,681 | 48,191 | 47,590 | 46,776 | 46,543 |
Source: Population Division, U.S. Census Bureau