|No. of teams||12|
|Trenton Thunder (2019)|
|Most titles||Binghamton Triplets (10)|
The Eastern League is a Minor League Baseball league, which operates primarily in the northeastern United States, although it has had a team in Ohio since 1989. The Eastern League has played at the Double-A level since 1963. The league was founded in 1923, as the New York-Pennsylvania League. In 1936, the first team outside the two original states was created, when the York White Roses of York, Pennsylvania, moved to Trenton, New Jersey, and was renamed the Trenton Senators. In 1938, when the Scranton Miners of Scranton, Pennsylvania, moved to Hartford, Connecticut, and became the Hartford Bees, the league was renamed the Eastern League.
Since 1923, there have been Eastern League teams in 51 different cities, located in 12 different states and two Canadian provinces. The league consisted of six to eight teams from 1923 until 1993. In 1994, the league expanded to 10 teams, with the addition of the Portland Sea Dogs and the New Haven Ravens, and split into two divisions, the Northern Division and the Southern Division. In 1999, the league expanded to 12 teams, with the addition of the Altoona Curve and the Erie SeaWolves. The two divisions were restructured and renamed for the 2010 season, as the Eastern Division and the Western Division, because the Connecticut Defenders moved to Richmond, Virginia, after the 2009 season, where they are now known as the Richmond Flying Squirrels.
|Current team locations:|
|Eastern||Binghamton Rumble Ponies||New York Mets||Binghamton, New York||NYSEG Stadium||6,012|
|Hartford Yard Goats||Colorado Rockies||Hartford, Connecticut||Dunkin' Donuts Park||6,121|
|New Hampshire Fisher Cats||Toronto Blue Jays||Manchester, New Hampshire||Northeast Delta Dental Stadium||6,500|
|Portland Sea Dogs||Boston Red Sox||Portland, Maine||Hadlock Field||7,368|
|Reading Fightin Phils||Philadelphia Phillies||Reading, Pennsylvania||FirstEnergy Stadium||9,000|
|Trenton Thunder||New York Yankees||Trenton, New Jersey||Arm & Hammer Park||6,341|
|Western||Akron RubberDucks||Cleveland Indians||Akron, Ohio||Canal Park||7,630|
|Altoona Curve||Pittsburgh Pirates||Altoona, Pennsylvania||Peoples Natural Gas Field||7,210|
|Bowie Baysox||Baltimore Orioles||Bowie, Maryland||Prince George's Stadium||10,000|
|Erie SeaWolves||Detroit Tigers||Erie, Pennsylvania||UPMC Park||6,000|
|Harrisburg Senators||Washington Nationals||Harrisburg, Pennsylvania||FNB Field||6,187|
|Richmond Flying Squirrels||San Francisco Giants||Richmond, Virginia||The Diamond||9,560|
Notes: This list includes teams in predecessor New York-Pennsylvania League of 1923 to 1937.
Bold font indicates that team is an active Eastern League team.
A "^" indicates that team's article redirects to an article of an active Eastern League team.
A "+" indicates that team's article redirects to an article of a defunct Eastern League team.
League champions have been determined by different means since the Eastern League's formation in 1923. Before 1934, the champions were simply the league pennant winners. A formal playoff system to determine league champions was established in 1934.
The Binghamton Triplets won 10 championships, the most among all teams in the league, followed by the Elmira Colonels/Pioneers/Royals (8) and the Scranton Miners/Red Sox (7). Among active franchises, the Harrisburg Senators have won 6 championships, the most in the league, followed by the Akron Aeros/RubberDucks (5) and the Reading Fightin Phils and Trenton Thunder (4).