List of best Major League Baseball season won-loss records Season records Season records

| Year_ | Franchise | League | Percentage | Finish |
|---|---|---|---|---|
| 1906 | Chicago Cubs | NL | .763 | Lost 1906 World Series |
| 1902 | Pittsburgh Pirates | NL | .741 | National League Champions |
| 1886 | Chicago White Stockings | NL | .726 | Lost 1886 World Series |
| 1909 | Pittsburgh Pirates | NL | .724 | Won 1909 World Series |
| 1954 | Cleveland Indians | AL | .721 | Lost 1954 World Series |
| 2001 | Seattle Mariners | AL | .716 | Lost 2001 ALCS |
| 1927 | New York Yankees | AL | .714 | Won 1927 World Series |
| 1886 | Detroit Wolverines | NL | .707 | 2nd place in National League |
| 1897 | Boston Beaneaters | NL | .705 | Lost 1897 Temple Cup |
| 1907 | Chicago Cubs | NL | .704 | Won 1907 World Series |
| 1931 | Philadelphia Athletics | AL | .704 | Lost 1931 World Series |