This list includes single-division League Championships, even if there was no postseason series thereafter. It also includes teams that finished 1st, in either half or overall, in the strike-shortened seasons of 1981 and 1994. And it includes teams that reached but lost single-game or best-2-out-of-3 Playoffs in the Pre-Wild Card Era. Ties in rankings broken by most recent, regardless of head-to-head matchups.
1. New York Yankees, 57: 1921, 1922, 1923, 1926, 1927, 1928, 1932, 1936, 1937, 1938, 1939, 1941, 1942, 1943, 1947, 1949, 1950, 1951, 1952, 1953, 1955, 1956, 1957, 1958, 1960, 1961, 1962, 1963, 1964, 1976, 1977, 1978, 1980, 1981, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010, 2011, 2012, 2015, 2017, 2018, 2019, 2020.
2. St. Louis Cardinals, 34: 1885, 1886, 1887, 1888, 1926, 1928, 1930, 1931, 1934, 1942, 1943, 1944, 1946, 1964, 1967, 1968, 1982, 1985, 1987, 1996, 2000, 2001, 2002, 2004, 2005, 2006, 2009, 2011, 2012, 2013, 2014, 2015, 2019, 2020.
3. Chicago Cubs, 30: 1870, 1871, 1876, 1880, 1881, 1882, 1885, 1886, 1906, 1907, 1908, 1910, 1918, 1929, 1932, 1935, 1938, 1945, 1984, 1989, 1998, 2003, 2007, 2008, 2015, 2016, 2017, 2018, 2020.
4. Los Angeles Dodgers, 28: 1959, 1962, 1963, 1965, 1966, 1974, 1977, 1978, 1980, 1981, 1983, 1985, 1988, 1994, 1995, 1996, 2004, 2006, 2008, 2009, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020. Counting the Brooklyn Dodgers, 1889, 1890, 1899, 1900, 1916, 1920, 1941, 1946, 1947, 1949, 1951, 1952, 1953, 1955, 1956, that's 43.
5. Boston Red Sox, 27: 1903, 1904, 1912, 1915, 1916, 1918, 1946, 1948, 1967, 1975, 1978, 1986, 1988, 1990, 1995, 1998, 1999, 2003, 2004, 2005, 2007, 2008, 2009, 2013, 2016, 2017, 2018.
6. Atlanta Braves, 22: 1969, 1982, 1991, 1992, 1993, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2010, 2012, 2013, 2018, 2019, 2020. Counting the Boston Braves, 1872, 1873, 1874, 1875, 1877, 1878, 1883, 1891, 1892, 1893, 1897, 1898, 1914, 1948; and the Milwaukee Braves, 1957, 1958, 1959; that's 39.
7. Oakland Athletics, 21: 1971, 1972, 1973, 1974, 1975, 1981, 1988, 1989, 1990, 1992, 2000, 2001, 2002, 2003, 2006, 2012, 2013, 2014, 2018, 2019, 2020. Counting the Philadelphia Athletics, 1902, 1905, 1910, 1911, 1913, 1914, 1929, 1930, 1931, that's 30.
8. Cincinnati Reds, 20: 1882, 1919, 1939, 1940, 1961, 1970, 1972, 1973, 1975, 1976, 1979, 1981, 1990, 1994, 1995, 1999, 2010, 2012, 2013, 2020.
9. Pittsburgh Pirates, 19: 1901, 1902, 1903, 1909, 1925, 1927, 1960, 1970, 1971, 1972, 1974, 1975, 1979, 1990, 1991, 1992, 2013, 2014, 2015.
10. Detroit Tigers, 17: 1907, 1908, 1909, 1934, 1935, 1940, 1945, 1968, 1972, 1984, 1987, 2006, 2009, 2011, 2012, 2013, 2014.
11. Minnesota Twins, 15: 1965, 1969, 1970, 1987, 1991, 2002, 2003, 2004, 2006, 2008, 2009, 2010, 2017, 2019, 2020. Counting the Washington Senators, 1924, 1925 and 1933, that's 18.
12. Cleveland Indians, 15: 1920, 1948, 1954, 1995, 1996, 1997, 1998, 1999, 2001, 2007, 2013, 2016, 2017, 2018, 2020.
13. Houston Astros, 14: 1980, 1981, 1986, 1997, 1998, 1999, 2001, 2004, 2005, 2015, 2017, 2018, 2019, 2020.
14. Philadelphia Phillies, 14: 1915, 1950, 1976, 1977, 1978, 1980, 1981, 1983, 1993, 2007, 2008, 2009, 2010, 2011.
15. Baltimore Orioles, 13: 1966, 1969, 1970, 1971, 1973, 1974, 1979, 1983, 1996, 1997, 2012, 2014, 2016. Counting the St. Louis Browns, 1944, that's 14.
16. Chicago White Sox, 12: 1901, 1906, 1917, 1919, 1959, 1983, 1993, 1994, 2000, 2005, 2008, 2020.
17. San Francisco Giants, 12: 1962, 1971, 1987, 1989, 1997, 2000, 2002, 2003, 2010, 2012, 2014, 2016. Counting the New York Giants, 1888, 1889, 1894, 1904, 1905, 1908, 1911, 1912, 1913, 1917, 1921, 1922, 1923, 1924, 1933, 1936, 1937, 1951, 1954, that's 31.
18. Los Angeles Angels, 11: 1979, 1982, 1986, 1995, 2002, 2004, 2005, 2007, 2008, 2009, 2014.
19. Texas Rangers, 9: 1994, 1996, 1998, 1999, 2010, 2011, 2012, 2015, 2016.
20. New York Mets, 9: 1969, 1973, 1986, 1988, 1999, 2000, 2006, 2015, 2016.
21. Kansas City Royals, 9: 1976, 1977, 1978, 1980, 1981, 1984, 1985, 2014, 2015.
22. Toronto Blue Jays, 8: 1985, 1989, 1991, 1992, 1993, 2015, 2016, 2020.
23. Milwaukee Brewers, 7: 1981, 1982, 2008, 2011, 2018, 2019, 2020.
24. San Diego Padres, 7: 1984, 1996, 1998, 2005, 2006, 2007, 2020.
25. Tampa Bay Rays, 6: 2008, 2010, 2011, 2013, 2019, 2020.
26. Arizona Diamondbacks, 6: 1999, 2001, 2002, 2007, 2011, 2017.
27. Washington Nationals, 5: 2012, 2014, 2016, 2017, 2019. Counting the Montreal Expos, 1981 and 1994, that's 7.
28. Colorado Rockies, 5: 1995, 2007, 2009, 2017, 2018.
29. Seattle Mariners, 4: 1995, 1997, 2000, 2001.
30. Miami Marlins, 3: 1997, 2003, 2020.
*
Overall, in all cities:
1. Yankees, 57.
2. Dodgers, 43.
3. Braves, 39.
4. Cardinals, 34.
5. Giants, 31.
6. A's, 30.
7. Cubs, 30.
8. Red Sox, 27.
9. Reds, 20.
10. Pirates, 19.
11. Twins, 18.
12. Tigers, 17.
13. Indians, 15.
14. Astros, 14.
15. Phillies, 14.
16. Orioles, 14.
17. White Sox, 12.
18. Angels, 11,
19. Rangers, 9.
20. Mets, 9.
21. Royals, 9.
22. Blue Jays, 8.
23. Brewers, 7.
24. Padres, 7.
25. Nationals, 7.
26. Rays, 6.
27. Diamondbacks, 6.
28. Rockies, 5.
29. Mariners, 4.
30. Marlins, 3.