| | Anaheim Angels, see Los Angeles Angels |
| 1 | Arizona Diamondbacks | 1998 | 2021 | 3,727 | 1,820 | 1,907 | .488 | -87 | 5 | 1 | 1 | 6 | 530 | 2 | 16,921 | 127,457 | 32,618 | 3,944 | .256 | 17,187 | 4.25 |
| 2 | Atlanta Braves | 1876 | 2021 | 21,672 | 10,782 | 10,736 | .501 | 46 | 20 | 17 | 3 | 26 | 2050 | 53 | 96,578 | 742,088 | 192,819 | 14,145 | .260 | 95,663 | 3.67 |
| | Also played as Milwaukee Braves, Boston Braves, Boston Bees, Boston Rustlers, Boston Doves, Boston Beaneaters and Boston Red Stockings |
| 3 | Baltimore Orioles | 1901 | 2021 | 18,766 | 8,828 | 9,828 | .473 | -1000 | 9 | 7 | 3 | 14 | 1893 | 34 | 80,914 | 637,533 | 164,775 | 13,710 | .258 | 86,331 | 4.05 |
| | Also played as St. Louis Browns and Milwaukee Brewers |
| | Boston Braves, see Atlanta Braves |
| 4 | Boston Red Sox | 1901 | 2021 | 18,756 | 9,689 | 8,984 | .519 | 705 | 10 | 14 | 9 | 24 | 1853 | 37 | 87,573 | 641,875 | 171,484 | 13,925 | .267 | 83,949 | 3.91 |
| | Also played as Boston Americans |
| | Brooklyn Dodgers, see Los Angeles Dodgers |
| | California Angels, see Los Angeles Angels |
| 5 | Chicago Cubs | 1876 | 2021 | 21,710 | 11,066 | 10,483 | .514 | 583 | 8 | 17 | 3 | 21 | 2142 | 45 | 99,946 | 743,231 | 194,951 | 14,580 | .262 | 96,405 | 3.68 |
| | Also played as Chicago Orphans, Chicago Colts and Chicago White Stockings |
| 6 | Chicago White Sox | 1901 | 2021 | 18,763 | 9,378 | 9,282 | .503 | 96 | 5 | 6 | 3 | 10 | 1816 | 32 | 81,796 | 635,373 | 165,371 | 11,714 | .260 | 81,400 | 3.78 |
| 7 | Cincinnati Reds | 1882 | 2021 | 21,293 | 10,683 | 10,471 | .505 | 212 | 10 | 10 | 5 | 16 | 2056 | 36 | 95,580 | 725,966 | 189,555 | 13,652 | .261 | 94,681 | 3.75 |
| | Also played as Cincinnati Redlegs and Cincinnati Red Stockings |
| 8 | Cleveland Indians | 1901 | 2021 | 18,764 | 9,562 | 9,111 | .512 | 451 | 10 | 6 | 2 | 15 | 1935 | 34 | 84,970 | 639,802 | 169,724 | 13,353 | .265 | 82,866 | 3.83 |
| | Also played as Cleveland Naps, Cleveland Bronchos and Cleveland Blues |
| 9 | Colorado Rockies | 1993 | 2021 | 4,475 | 2,103 | 2,372 | .470 | -269 | 0 | 1 | 0 | 5 | 604 | 1 | 22,515 | 153,988 | 42,069 | 5,111 | .273 | 23,602 | 4.97 |
| 10 | Detroit Tigers | 1901 | 2021 | 18,792 | 9,418 | 9,281 | .504 | 137 | 7 | 11 | 4 | 16 | 1733 | 24 | 86,625 | 641,168 | 169,950 | 14,024 | .265 | 86,199 | 4.00 |
| 11 | Houston Astros | 1962 | 2021 | 9,435 | 4,693 | 4,737 | .498 | -44 | 10 | 3 | 1 | 14 | 940 | 10 | 39,961 | 320,101 | 81,559 | 7,667 | .255 | 39,749 | 3.81 |
| | Also played as Houston Colt .45s |
| | Kansas City Athletics, see Oakland Athletics |
| 12 | Kansas City Royals | 1969 | 2021 | 8,285 | 3,971 | 4,312 | .479 | -341 | 8 | 4 | 2 | 9 | 934 | 4 | 36,354 | 283,767 | 74,844 | 6,442 | .264 | 38,234 | 4.25 |
| 13 | Los Angeles Angels | 1961 | 2021 | 9,592 | 4,786 | 4,803 | .499 | -17 | 9 | 1 | 1 | 10 | 1125 | 12 | 41,650 | 325,763 | 83,788 | 8,510 | .257 | 41,963 | 3.99 |
| | Also played as Los Angeles Angels of Anaheim, Anaheim Angels and California Angels |
| 14 | Los Angeles Dodgers | 1884 | 2021 | 21,094 | 11,079 | 9,876 | .529 | 1203 | 19 | 25 | 7 | 34 | 1883 | 50 | 94,758 | 718,772 | 187,888 | 13,267 | .261 | 89,388 | 3.53 |
| | Also played as Brooklyn Dodgers, Brooklyn Robins, Brooklyn Superbas, Brooklyn Bridegrooms, Brooklyn Grooms, Brooklyn Grays and Brooklyn Atlantics |
| 15 | Miami Marlins | 1993 | 2021 | 4,466 | 2,065 | 2,401 | .462 | -336 | 0 | 2 | 2 | 3 | 651 | 5 | 18,985 | 151,992 | 38,957 | 4,048 | .256 | 20,711 | 4.30 |
| | Also played as Florida Marlins |
| | Milwaukee Braves, see Atlanta Braves |
| 16 | Milwaukee Brewers | 1969 | 2021 | 8,296 | 4,002 | 4,290 | .483 | -288 | 4 | 1 | 0 | 7 | 955 | 7 | 36,792 | 281,893 | 72,479 | 8,031 | .257 | 37,897 | 4.17 |
| | Also played as Seattle Pilots |
| | Milwaukee Brewers (1901), see Baltimore Orioles |
| 17 | Minnesota Twins | 1901 | 2021 | 18,778 | 8,982 | 9,687 | .481 | -705 | 12 | 6 | 3 | 17 | 1738 | 25 | 82,514 | 640,791 | 168,392 | 11,300 | .263 | 85,874 | 3.99 |
| | Also played as Washington Senators |
| | Montreal Expos, see Washington Nationals |
| | New York Giants, see San Francisco Giants |
| 18 | New York Mets | 1962 | 2021 | 9,424 | 4,528 | 4,888 | .481 | -360 | 6 | 5 | 2 | 9 | 1145 | 15 | 38,619 | 318,985 | 79,759 | 7,867 | .250 | 39,636 | 3.79 |
| 19 | New York Yankees | 1903 | 2021 | 18,466 | 10,464 | 7,914 | .569 | 2550 | 19 | 40 | 27 | 56 | 1725 | 46 | 89,770 | 629,830 | 167,698 | 16,436 | .266 | 77,117 | 3.65 |
| | Also played as New York Highlanders |
| 20 | Oakland Athletics | 1901 | 2021 | 18,730 | 9,121 | 9,522 | .489 | -401 | 17 | 15 | 9 | 29 | 2002 | 41 | 83,015 | 635,267 | 164,085 | 13,506 | .258 | 85,378 | 3.98 |
| | Also played as Kansas City Athletics and Philadelphia Athletics |
| | Philadelphia Athletics, see Oakland Athletics |
| 21 | Philadelphia Phillies | 1883 | 2021 | 21,100 | 9,903 | 11,082 | .472 | -1179 | 12 | 7 | 2 | 14 | 2117 | 35 | 93,504 | 722,100 | 188,162 | 13,436 | .261 | 99,518 | 3.99 |
| | Also played as Philadelphia Quakers |
| 22 | Pittsburgh Pirates | 1882 | 2021 | 21,251 | 10,602 | 10,509 | .502 | 93 | 9 | 9 | 5 | 17 | 2035 | 40 | 94,833 | 728,523 | 192,377 | 11,702 | .264 | 94,546 | 3.74 |
| | Also played as Pittsburgh Alleghenys |
| 23 | San Diego Padres | 1969 | 2021 | 8,302 | 3,843 | 4,457 | .463 | -614 | 5 | 2 | 0 | 6 | 1071 | 12 | 33,397 | 280,733 | 70,018 | 6,616 | .249 | 36,439 | 3.96 |
| 24 | San Francisco Giants | 1883 | 2021 | 21,176 | 11,257 | 9,756 | .536 | 1501 | 8 | 23 | 8 | 26 | 1855 | 57 | 98,053 | 723,071 | 190,684 | 14,914 | .264 | 90,676 | 3.58 |
| | Also played as New York Giants and New York Gothams |
| 25 | Seattle Mariners | 1977 | 2021 | 7,006 | 3,301 | 3,703 | .471 | -402 | 3 | 0 | 0 | 4 | 921 | 6 | 31,129 | 239,365 | 61,976 | 7,004 | .259 | 33,030 | 4.34 |
| | Seattle Pilots, see Milwaukee Brewers |
| | St. Louis Browns, see Baltimore Orioles |
| 26 | St. Louis Cardinals | 1882 | 2021 | 21,293 | 10,999 | 10,142 | .520 | 857 | 14 | 23 | 11 | 30 | 2158 | 47 | 97,655 | 730,131 | 194,230 | 12,464 | .266 | 93,764 | 3.68 |
| | Also played as St. Louis Perfectos, St. Louis Browns and St. Louis Brown Stockings |
| 27 | Tampa Bay Rays | 1998 | 2021 | 3,724 | 1,786 | 1,938 | .480 | -152 | 3 | 2 | 0 | 6 | 530 | 1 | 16,497 | 126,838 | 32,358 | 3,840 | .255 | 17,276 | 4.30 |
| | Also played as Tampa Bay Devil Rays |
| 28 | Texas Rangers | 1961 | 2021 | 9,580 | 4,558 | 5,016 | .476 | -458 | 7 | 2 | 0 | 8 | 1182 | 8 | 43,105 | 327,175 | 84,651 | 9,484 | .259 | 45,183 | 4.29 |
| | Also played as Washington Senators |
| 29 | Toronto Blue Jays | 1977 | 2021 | 7,002 | 3,465 | 3,534 | .495 | -69 | 6 | 2 | 2 | 8 | 862 | 8 | 32,401 | 240,092 | 62,543 | 7,562 | .260 | 32,212 | 4.24 |
| 30 | Washington Nationals | 1969 | 2021 | 8,290 | 4,049 | 4,237 | .489 | -188 | 5 | 1 | 1 | 6 | 976 | 10 | 34,769 | 280,520 | 71,270 | 7,066 | .254 | 35,626 | 3.89 |
| | Also played as Montreal Expos |
| | Washington Senators (1901-1960), see Minnesota Twins |
| | Washington Senators (1961-1971), see Texas Rangers |
Inactive Franchises