(Links below lead to Quick Facts for Massachusetts Counties: 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 |
| Massachusetts | 6,497,967 | 6,467,915 | 6,443,424 | 6,434,343 | 6,437,414 | 6,441,440 | 6,433,043 | 6,407,269 | 6,362,583 | 6,349,097 |
|---|---|---|---|---|---|---|---|---|---|---|
| Barnstable County | 221,049 | 221,990 | 223,315 | 224,913 | 226,829 | 228,135 | 227,002 | 225,042 | 223,228 | 222,230 |
| Berkshire County | 129,395 | 130,032 | 130,350 | 131,193 | 131,985 | 132,565 | 133,083 | 133,718 | 134,787 | 134,953 |
| Bristol County | 545,823 | 545,212 | 544,641 | 545,499 | 546,204 | 546,393 | 543,063 | 538,640 | 536,069 | 534,678 |
| Dukes County | 15,527 | 15,452 | 15,390 | 15,467 | 15,480 | 15,458 | 15,361 | 15,192 | 15,076 | 14,987 |
| Essex County | 736,457 | 732,575 | 731,179 | 730,552 | 731,206 | 732,496 | 733,216 | 730,862 | 725,341 | 723,419 |
| Franklin County | 71,735 | 71,647 | 71,693 | 71,937 | 71,950 | 71,904 | 71,887 | 71,669 | 71,493 | 71,535 |
| Hampden County | 460,840 | 460,629 | 460,727 | 460,217 | 460,088 | 460,041 | 458,747 | 456,361 | 456,565 | 456,228 |
| Hampshire County | 154,983 | 154,665 | 154,295 | 153,777 | 153,776 | 153,671 | 152,894 | 152,265 | 152,379 | 152,251 |
| Middlesex County | 1,482,478 | 1,469,798 | 1,463,654 | 1,462,024 | 1,465,147 | 1,468,316 | 1,472,688 | 1,475,675 | 1,469,120 | 1,465,396 |
| Nantucket County | 11,215 | 11,060 | 10,820 | 10,610 | 10,541 | 10,309 | 10,082 | 9,743 | 9,571 | 9,520 |
| Norfolk County | 659,909 | 655,358 | 652,980 | 651,429 | 652,805 | 653,262 | 654,076 | 653,500 | 651,212 | 650,308 |
| Plymouth County | 492,066 | 489,808 | 488,294 | 487,765 | 486,180 | 485,029 | 482,750 | 478,807 | 474,365 | 472,822 |
| Suffolk County | 732,684 | 727,546 | 715,450 | 711,331 | 709,969 | 711,347 | 710,660 | 704,979 | 690,721 | 689,807 |
| Worcester County | 783,806 | 782,143 | 780,636 | 777,629 | 775,254 | 772,514 | 767,534 | 760,816 | 752,656 | 750,963 |
Source: Population Division, U.S. Census Bureau