List of defunct and relocated Major League Baseball teams

Throughout the history of Major League Baseball, numerous franchises have moved or become defunct.

The Baltimore Orioles went defunct after the 1902 season, representing the most recent time that an NL or AL team ceased operations.

In 2025, the Oakland Athletics plan to temporarily move to West Sacramento, California, and brand themselves as simply the "A's" and "Athletics" with no city name attached, until they permanently move to Las Vegas in 2028 or later when their new ballpark is completed.

Franchises that played only as associate clubs of a major league are not included.

[43] The Special Records Committee excluded the National Association (NA), which operated from 1871 to 1875, as a major league.

Multiple bars for a city indicates that the city hosted multiple major league franchises at the same time; for example, Philadelphia at times hosted two or three franchises concurrently.