9 league titles: 2018, 2013, 2007, 2004, 1918, 1916, 1915, 1912, 1903.
Franchise history
Regular-season record. Division finish uses that season's division alignment.
| 2026 | 87 | 75 | 0 | .537 | 3rd AL East | Playoffs0-2 |
| 2025 | 89 | 73 | 0 | .549 | 3rd AL East | Playoffs1-2 |
| 2024 | 81 | 81 | 0 | .500 | 3rd AL East | — |
| 2023 | 78 | 84 | 0 | .481 | 5th AL East | — |
| 2022 | 78 | 84 | 0 | .481 | 5th AL East | — |
| 2021 | 92 | 70 | 0 | .568 | 2nd AL East | Playoffs6-5 |
| 2020 | 24 | 36 | 0 | .400 | 5th AL East | — |
| 2019 | 84 | 78 | 0 | .519 | 3rd AL East | — |
| 2018 | 108 | 54 | 0 | .667 | 1st AL East | Champions11-3 |
| 2017 | 93 | 69 | 0 | .574 | 1st AL East | Playoffs1-3 |
| 2016 | 93 | 69 | 0 | .574 | 1st AL East | Playoffs0-3 |
| 2015 | 78 | 84 | 0 | .481 | 5th AL East | — |
| 2014 | 71 | 91 | 0 | .438 | 5th AL East | — |
| 2013 | 97 | 65 | 0 | .599 | 1st AL East | Champions11-5 |
| 2012 | 69 | 93 | 0 | .426 | 5th AL East | — |
| 2011 | 90 | 72 | 0 | .556 | 3rd AL East | — |
| 2010 | 89 | 73 | 0 | .549 | 3rd AL East | — |
| 2009 | 95 | 67 | 0 | .586 | 2nd AL East | Playoffs0-3 |
| 2008 | 95 | 67 | 0 | .586 | 2nd AL East | Playoffs6-5 |
| 2007 | 96 | 66 | 0 | .593 | 1st AL East | Champions11-3 |
| 2006 | 86 | 76 | 0 | .531 | 3rd AL East | — |
| 2005 | 95 | 67 | 0 | .586 | 1st AL East | Playoffs0-3 |
| 2004 | 98 | 64 | 0 | .605 | 2nd AL East | Champions11-3 |
| 2003 | 95 | 67 | 0 | .586 | 2nd AL East | Playoffs6-6 |
| 2002 | 93 | 69 | 0 | .574 | 2nd AL East | — |
| 2001 | 82 | 79 | 0 | .509 | 2nd AL East | — |
| 2000 | 85 | 77 | 0 | .525 | 2nd AL East | — |
| 1999 | 94 | 68 | 0 | .580 | 2nd AL East | Playoffs4-6 |
| 1998 | 92 | 70 | 0 | .568 | 2nd AL East | Playoffs1-3 |
| 1997 | 78 | 84 | 0 | .481 | 4th AL East | — |
| 1996 | 85 | 77 | 0 | .525 | 3rd AL East | — |
| 1995 | 86 | 58 | 0 | .597 | 1st AL East | Playoffs0-3 |
| 1994 | 54 | 61 | 0 | .470 | 4th AL East | — |
| 1993 | 80 | 82 | 0 | .494 | 5th AL East | — |
| 1992 | 73 | 89 | 0 | .451 | 7th AL East | — |
| 1991 | 84 | 78 | 0 | .519 | 2nd AL East | — |
| 1990 | 88 | 74 | 0 | .543 | 1st AL East | Playoffs0-4 |
| 1989 | 83 | 79 | 0 | .512 | 3rd AL East | — |
| 1988 | 89 | 73 | 0 | .549 | 1st AL East | Playoffs0-4 |
| 1987 | 78 | 84 | 0 | .481 | 5th AL East | — |
| 1986 | 95 | 66 | 0 | .590 | 1st AL East | Lost final7-7 |
| 1985 | 81 | 81 | 1 | .500 | 5th AL East | — |
| 1984 | 86 | 76 | 0 | .531 | 4th AL East | — |
| 1983 | 78 | 84 | 0 | .481 | 6th AL East | — |
| 1982 | 89 | 73 | 0 | .549 | 3rd AL East | — |
| 1981 | 59 | 49 | 0 | .546 | 5th AL East | — |
| 1980 | 83 | 77 | 0 | .519 | 4th AL East | — |
| 1979 | 91 | 69 | 0 | .569 | 3rd AL East | — |
| 1978 | 99 | 64 | 0 | .607 | 2nd AL East | — |
| 1977 | 97 | 64 | 0 | .602 | 3rd AL East | — |
| 1976 | 83 | 79 | 0 | .512 | 3rd AL East | — |
| 1975 | 95 | 65 | 0 | .594 | 1st AL East | Lost final6-4 |
| 1974 | 84 | 78 | 0 | .519 | 3rd AL East | — |
| 1973 | 89 | 73 | 0 | .549 | 2nd AL East | — |
| 1972 | 85 | 70 | 0 | .548 | 2nd AL East | — |
| 1971 | 85 | 77 | 0 | .525 | 3rd AL East | — |
| 1970 | 87 | 75 | 0 | .537 | 3rd AL East | — |
| 1969 | 87 | 75 | 0 | .537 | 3rd AL East | — |
