Major League Baseball schedule

The Major League Baseball season schedule consists of 162 games for each of the 30 teams in the American League and National League, played over approximately six months – a total of 2,430 games, plus the postseason. The regular season runs from late March/early April to late September/early October, followed by the postseason which can run to early November. The season begins with the official Opening Day, and, as of 2018, runs 26½ weeks through the last Sunday of September or first Sunday of October. One or more International Opener games may be scheduled outside the United States or Canada before the official Opening Day. It is possible for a given team to play a maximum of 22 games in the postseason in a given year, provided the team is a wild card and advances to each of the Division Series, Championship Series, and World Series with each series going the distance.
The regular season is constructed from series. Due to travel concerns and the sheer number of games, pairs of teams are never scheduled to play single games against each other ; instead they play games on several consecutive days in the same ballpark. Teams play one mid-week series and one weekend series per week. Depending on the length of the series, mid-week series games are usually scheduled between Monday and Thursday, while weekend games are scheduled between Thursday and Monday. Teams play for 26½ weeks. Due to the mid-week all-star break in July, teams are scheduled to play 27 weekend series and 25 mid-week series for 52 total series. A team's road games are usually grouped into a multi-series road trip; home series are grouped into homestands.
Beginning with the 2025 season, teams play a balanced schedule as follows: thirteen games are played against each of the other four teams in their own division, six or seven games against each of the other ten teams in their own league, six games against one "geographic rival" from the other league, and three games against each of the other fourteen teams from the other league, for 48 total interleague games. Under this schedule, divisional games consist of two, three or four-game series, intraleague games consist of three or four-game series, and the interleague games consist of two three-game series against the geographic rival and a single three-game series against the other interleague opponents.
Note that rainouts and other cancellations are often rescheduled when needed during the season, sometimes as doubleheaders. However, if two teams are scheduled to meet for the final time in the last two weeks of the season, and the game is cancelled, it may not be rescheduled if there is no impact on the divisional or wild card races. Both examples occurred in 2024. The September 29 game between the Houston Astros and the Cleveland Guardians was cancelled due to rain. As the game was scheduled on the last day of the regular season, and it did not affect the postseason seeding for both teams, the game was not rescheduled. In contrast, two NL East division games between the New York Mets and the Atlanta Braves needed to be made up following the last day of the regular season because it played a part in the wild card race involving the Mets, the Braves, and the Arizona Diamondbacks.
From 1953 to 1981, Harry Simmons was responsible for devising the Major League Baseball schedule. Henry and Holly Stephenson, a husband-and-wife team, were in charge of constructing the MLB calendar for over two decades. For the 2005 schedule, the MLB selected the Sports Scheduling Group, a small company located outside Pittsburgh, to craft the schedule for that year. Each year, the MLB considers the scheduling proposals from various external groups.
The upcoming MLB regular season schedule is usually released while the current regular season is ongoing, typically after the All-Star Game or later. In contrast, the National Football League, National Hockey League and National Basketball Association release their schedules in the offseason.

19th century

This account gives the length of the major league "championship season" schedule by league and year. During this era, there were a number of different leagues that would be deemed Major League.
Prior to the first league schedule in 1877, member clubs scheduled their own matches by mutual arrangement, including championship games necessarily with member clubs, other games with members, and games with non-member clubs. Some may have practically dictated their arrangements with some others, but there was no central control or coordination.
The listed years are those in which the league revised its schedule. For example, the National League scheduled 84 games during 1879, 1880, 1881, and 1882 – that is, four seasons from 1879, ending before 1883, the next listing. 1876 is listed here for convenience although the NL did not schedule games.

National Association of Professional Base Ball Players (1871–1875)

The National Association of Professional Base Ball Players did not schedule games, nor did it control the number of teams, a major reason for its demise after the 1875 season. Clubs paid a $10 entry fee, later $20, to enter the Association for one season, and thereby declare for that year's national championship. Without continuing membership or heavy investment, there was little to deter a team from breaking a commitment, and though it happened, it was mainly due to clubs going out of business.
This listing gives the greatest number of games played by any club for each season. Naturally, the leader by games played was always a strong club fielding one of the better gate attractions.
The leading numbers of games played to a decision were 33, 54, 59, 71, and 70 decisions; by the listed teams except the Mutuals in 1872.

National League (first 25 years of 1876–present)

The National League organized for 1876 on a different basis than the NAPBBP, granting exclusive memberships to eight clubs that would continue from year to year – it was generally expected, if only because membership would be profitable. But in its first season in 1876, the new league followed its predecessor in merely agreeing that each club would play a certain number of matches to a decision by a certain date. Boston played 70 games with its quota of ten decisions against every rival. The others achieved 56 to 68 decisions with 64 to 66 for the four western teams as the teams from New York and Philadelphia abandoned their schedule-concluding road trips.

Start year	Total Games	Schedule
1876	70	quota of up to 10 games × 7 opponents – matches independently scheduled by clubs
1877	60	contraction – 12 games × 5 opponents
1879	84	expansion – 12 games × 7 opponents
1883	98	14 games × 7 opponents
1884	112	16 games × 7 opponents
1886	126	18 games × 7 opponents
1888	140	20 games × 7 opponents
1892	154	expansion – 14 games × 11 opponents
1893	132	12 games × 11 opponents
1898	154	14 games × 11 opponents

American Association (1882–1891)

Start year	Total Games	Schedule
1882	80	16 games × 5 opponents
1883	98	expansion – 14 games × 7 opponents
1884	110	expansion – 10 games × 11 opponents
1885	112	contraction – 16 games × 7 opponents
1886	140	20 games × 7 opponents

The AA expanded its schedule to 140 games two years before the National League did so. After 1891 this incarnation of the AA dissolved with four teams bought out and four others joining the NL, nominally creating one big league, the "National League and American Association" of 12 clubs.

Union Association (1884)

Players' League (1890)

20th & 21st centuries

This account gives the originally announced length of the major league "championship season" schedule by league and year.
This does not include later announced curtailments of play by war or by strikes and lockouts. The schedules for 1995 were revised and shortened from 162 to 144 games, after late resolution of the strike that had begun in 1994 required a delay in the season to accommodate limited spring training.

National League

American League

Recent season schedules

Since 1998, there have been 30 major league teams with a single advance schedule for every season that comprises 2,430 games. Each team plays 162 games, 81 as the "home" team, 81 as the "visitor". Occasionally, the advance schedule is subsequently altered due to a game postponement or a one-game tie-breaker to determine which team will play in the postseason.

1998 to 2012

Before 2013, the schedule included 252 "interleague games" that matched one team from the American League and one from the National League; the other 2,178 games matched a pair from within one league. About half of the latter matched teams from within one division and about half matched teams from different divisions in one league. These interleague games were played from mid-to-late May to late June or early July.

1998 to 2004

There were different formats nearly every year between 1998 and 2004.
From 1998 to 2000, every pair of division rivals across all six divisions saw 11 or 12 games.
From 2001 to 2004, every pair of division rivals from the divisions with five teams saw 19 games. The AL West, which had four teams, saw 19 or 20 games, while the NL Central, which had six teams, would vary between 16 and 19 games, depending on the season.