Which MLB team has the longest streak of consecutive losing seasons?

The Pittsburgh Pirates have MLB’s longest streak of consecutive losing seasons, lasting 20 seasons from 1993 through 2012. The run began after Pittsburgh’s three straight National League East titles from 1990 through 1992 and ended when the Pirates finished 94–68 in 2013, earning their first winning record and playoff berth in more than two decades.

The streak was especially striking because the Pirates had been one of baseball’s strongest franchises in the previous generation. They won World Series titles in 1960, 1971, and 1979, and the early-1990s teams featured stars such as Barry Bonds, Bobby Bonilla, and Andy Van Slyke. After that core broke apart, Pittsburgh struggled with roster turnover, limited payroll, and difficult rebuilding years.

The Pirates came close to breaking the streak several times. Their best records during the stretch were 79–83 in both 1997 and 2012, just three victories short of a winning season. The statistic refers to finishing below .500, not necessarily losing 90 or 100 games; a team can have a losing season by only a few games.