How Many Innings in a World Series Game? Explained

By Emma Wilson · November 13, 2027

The World Series, Major League Baseball's championship series, consists of a best-of-seven format, meaning up to seven games are played to determine the champion. A team must win four games to claim the title, and the series ends as soon as one team reaches four wins. There is no fixed number of innings per game—each game lasts nine innings unless tied, in which case extra innings are played until a winner is decided.

Understanding the Structure of the World Series

The World Series is the annual championship series of Major League Baseball (MLB), contested between the champions of the American League (AL) and the National League (NL). Since its inception in 1903, the format has evolved, but the current structure has remained consistent: a best-of-seven series.

Key Facts About the World Series Format

The first team to win four games wins the World Series.
The series can last a minimum of four games and a maximum of seven.
Games are typically scheduled every day or every other day, depending on travel and broadcast needs.
If a game is tied after nine innings, it continues into extra innings until a winner is determined.
There is no time limit or inning cap on individual games.

How Many Innings Are Played Per Game?

Each World Series game follows standard MLB rules: nine regulation innings. If the score is tied after nine innings, the game continues into extra innings until one team leads at the end of a completed inning.

Extra Innings Rules

Since 2020, MLB has implemented a rule to expedite extra-inning games: a runner is placed on second base at the start of each extra inning. This rule applies to all postseason games, including the World Series, to reduce game length and player fatigue.

Year	Teams	Games Played	Longest Game (Innings)	Duration (Hours:Minutes)
2021	Atlanta Braves vs. Houston Astros	6	9	3:43
2020	Los Angeles Dodgers vs. Tampa Bay Rays	6	9	3:35
2019	Washington Nationals vs. Houston Astros	7	10	4:17
2018	Boston Red Sox vs. Los Angeles Dodgers	5	13	7:20
2017	Houston Astros vs. Los Angeles Dodgers	7	10	5:17
2016	Chicago Cubs vs. Cleveland Indians	7	10	4:38

Table data source:1, 2

The table shows recent World Series results, highlighting that while most games conclude in nine innings, several have extended into extra innings. The 2018 Game 3 between the Red Sox and Dodgers lasted 13 innings, making it one of the longest in World Series history by innings. Despite the extra-inning rule introduced in 2020, some games still take considerable time due to strategic delays and high-pressure situations.

Historical Evolution of the World Series Format

The World Series began in 1903 as a best-of-nine series, won by the Boston Americans over the Pittsburgh Pirates. However, from 1905 onward, it was changed to the current best-of-seven format, with exceptions only in 1919–1921 when it reverted briefly to best-of-nine.

Notable Changes Over Time

1903: First World Series, best-of-nine format.
1905: Switched to best-of-seven, now standard.
1919–1921: Best-of-nine used again, then abandoned.
2020: Extra-inning runner rule introduced during pandemic season, continued afterward.

Frequently Asked Questions About the World Series

How many games are in the World Series?

The World Series is a best-of-seven series, so a maximum of seven games are played. The first team to win four games becomes the champion. The actual number of games can be four, five, six, or seven, depending on how quickly one team secures four wins.

How many innings are in a World Series game?

A standard World Series game consists of nine innings. If the game is tied after nine innings, it continues into extra innings until one team takes the lead at the end of a full inning. There is no limit to how many extra innings can be played.

What happens if the World Series goes to seven games?

If the series reaches seven games, the winner of Game 7 is crowned the World Series champion. Game 7 is often considered the most exciting and pressure-filled game in baseball. It has occurred 40 times in history, most recently in 2019 and 2016.

Has there ever been a World Series game with more than 12 innings?

Yes, there have been multiple World Series games exceeding 12 innings. The longest game by innings was Game 3 of the 2018 World Series between the Boston Red Sox and Los Angeles Dodgers, which lasted 18 innings. However, it was played over two days due to a suspension, and the official duration was recorded as 7 hours and 20 minutes.

Do all World Series games go the full nine innings?

Most do, but not all. Games can end early due to weather (if the game is official after five innings) or mercy rules in rare cases. However, under normal circumstances, all World Series games aim to complete nine innings. If tied, they continue until a winner is decided.