| Rank | Team | On-Base Percentage | Record |
| 1. | Milwaukee Brewers, 1971 | .2692 | 51-111 |
| 2. | Chicago Cubs, 1981 | .2707 | 41-121 |
| 3. | Washington Senators, 1968 | .2754 | 59-103 |
| 4. | New York Mets, 1968 | .2785 | 87-75 |
| 5. | San Diego Padres, 1969 | .2788 | 55-107 |
| 6. | Los Angeles Dodgers, 1967 | .2790 | 67-95 |
| 7. | Seattle Mariners, 1988 | .2795 | 55-107 |
| 8. | Seattle Mariners, 2011 | .2797 | 42-120 |
| 9. | Baltimore Orioles, 1959 | .2798 | 52-102 |
| 10. | Chicago Cubs, 1968 | .2812 | 65-97 |
| 11. | New York Yankees, 1966 | .2817 | 63-99 |
| 12. | New York Yankees, 1968 | .2824 | 74-88 |
| 13. | Los Angeles Dodgers, 1968 | .2824 | 66-96 |
| 14. | New York Mets, 1963 | .2843 | 54-108 |
| 15. | Cincinnati Reds, 1968 | .2844 | 72-90 |
| 16. | Washington Senators, 1958 | .2857 | 42-112 |
| 17. | San Francisco Giants, 1991 | .2859 | 68-94 |
| 18. | Atlanta Braves, 1974 | .2862 | 54-108 |
| 19. | Montreal Expos, 1972 | .2882 | 58-104 |
| 20. | Seattle Mariners, 2005 | .2882 | 42-120 |
| 21. | Washington Senators, 1967 | .2884 | 70-92 |
| 22. | Pittsburgh Pirates, 1942 | .2884 | 60-94 |
| 23. | New York Mets, 1967 | .2886 | 51-111 |
| 24. | Miami Marlins, 2013 | .2887 | 39-123 |
| 25. | Chicago Cubs, 1985 | .2887 | 59-103 |
| 26. | Washington Senators, 1971 | .2887 | 74-88 |
| 27. | Chicago Cubs, 1980 | .2889 | 57-105 |
| 28. | Boston Braves, 1943 | .2891 | 53-101 |
| 29. | Chicago White Sox, 1968 | .2892 | 77-85 |
| 30. | Seattle Mariners, 2010 | .2893 | 40-122 |
| 31. | New York Mets, 1965 | .2894 | 60-102 |
| 32. | Toronto Blue Jays, 2010 | .2901 | 53-109 |
| 33. | Chicago Cubs, 1982 | .2902 | 56-106 |
| 34. | Minnesota Twins, 1968 | .2915 | 76-86 |
| 35. | Los Angeles Dodgers, 1989 | .2917 | 65-97 |
| 36. | Miami Marlins, 2012 | .2921 | 52-110 |
| 37. | Baltimore Orioles, 1968 | .2921 | 82-80 |
| 38. | Kansas City Royals, 1992 | .2921 | 59-103 |
| 39. | Pittsburgh Pirates, 1968 | .2922 | 80-82 |
| 40. | Chicago Cubs, 1986 | .2926 | 62-100 |
| 41. | Texas Rangers, 1972 | .2928 | 74-88 |
| 42. | Chicago Cubs, 1983 | .2929 | 54-108 |
| 43. | New York Mets, 1966 | .2930 | 62-100 |
| 44. | Toronto Blue Jays, 1981 | .2931 | 66-96 |
| 45. | Montreal Expos, 1990 | .2932 | 52-110 |
| 46. | Chicago Cubs, 1978 | .2934 | 54-108 |
| 47. | Chicago White Sox, 1980 | .2935 | 56-106 |
| 48. | Minnesota Twins, 2013 | .2945 | 52-110 |
| 49. | Atlanta Braves, 1968 | .2947 | 74-88 |
| 50. | Atlanta Braves, 1988 | .2951 | 63-99 |