| 2013 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Hillsboro Hops, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians |
| 2012 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2011 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2010 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2009 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2008 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2007 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2006 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2005 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2004 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2003 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2002 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2001 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Salem-Keizer Volcanoes, Spokane Indians, Tri-City Dust Devils, Vancouver Canadians, Yakima Bears |
| 2000 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Portland Rockies, Salem-Keizer Volcanoes, Spokane Indians, Vancouver Canadians, Yakima Bears |
| 1999 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Portland Rockies, Salem-Keizer Volcanoes, Southern Oregon Timberjacks, Spokane Indians, Yakima Bears |
| 1998 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Portland Rockies, Salem-Keizer Volcanoes, Southern Oregon Timberjacks, Spokane Indians, Yakima Bears |
| 1997 |
A- |
Boise Hawks, Eugene Emeralds, Everett AquaSox, Portland Rockies, Salem-Keizer Volcanoes, Southern Oregon Timberjacks, Spokane Indians, Yakima Bears |
| 1996 |
A- |
Bellingham Giants, Boise Hawks, Eugene Emeralds, Everett AquaSox, Portland Rockies, Southern Oregon Timberjacks, Spokane Indians, Yakima Bears |
| 1995 |
A- |
Bellingham Giants, Boise Hawks, Eugene Emeralds, Everett AquaSox, Portland Rockies, Southern Oregon A's, Spokane Indians, Yakima Bears |
| 1994 |
A- |
Bellingham Mariners, Bend Rockies, Boise Hawks, Eugene Emeralds, Everett Giants, Southern Oregon A's, Spokane Indians, Yakima Bears |
| 1993 |
A- |
Bellingham Mariners, Bend Rockies, Boise Hawks, Eugene Emeralds, Everett Giants, Southern Oregon A's, Spokane Indians, Yakima Bears |
| 1992 |
A- |
Bellingham Mariners, Bend Rockies, Boise Hawks, Eugene Emeralds, Everett Giants, Southern Oregon A's, Spokane Indians, Yakima Bears |
| 1991 |
A- |
Bellingham Mariners, Bend Bucks, Boise Hawks, Eugene Emeralds, Everett Giants, Southern Oregon A's, Spokane Indians, Yakima Bears |
| 1990 |
A- |
Bellingham Mariners, Bend Bucks, Boise Hawks, Eugene Emeralds, Everett Giants, Southern Oregon A's, Spokane Indians, Yakima Bears |
| 1989 |
A- |
Bellingham Mariners, Bend Bucks, Boise Hawks, Eugene Emeralds, Everett Giants, Salem Dodgers, Southern Oregon A's, Spokane Indians |
| 1988 |
A- |
Bellingham Mariners, Bend Bucks, Boise Hawks, Eugene Emeralds, Everett Giants, Salem Dodgers, Southern Oregon A's, Spokane Indians |
| 1987 |
A- |
Bellingham Mariners, Bend Phillies, Boise Hawks, Eugene Emeralds, Everett Giants, Medford A's, Salem Angels, Spokane Indians |
| 1986 |
A- |
Bellingham Mariners, Bend Phillies, Eugene Emeralds, Everett Giants, Medford A's, Salem Angels, Spokane Indians, Tri-Cities Triplets |
| 1985 |
A- |
Bellingham Mariners, Bend Phillies, Eugene Emeralds, Everett Giants, Medford A's, Salem Angels, Spokane Indians, Tri-Cities Triplets |
| 1984 |
A- |
Bellingham Mariners, Bend Phillies, Eugene Emeralds, Everett Giants, Medford A's, Salem Angels, Spokane Indians, Tri-Cities Triplets |
| 1983 |
A- |
Bellingham Mariners, Bend Phillies, Eugene Emeralds, Medford A's, Salem Angels, Spokane Indians, Tri-Cities Triplets, Walla Walla Bears |
| 1982 |
A- |
Bellingham Mariners, Bend Phillies, Eugene Emeralds, Medford A's, Salem Angels, Walla Walla Padres |
| 1981 |
A- |
Bellingham Mariners, Bend Phillies, Eugene Emeralds, Medford A's, Salem Senators, Walla Walla Padres |
| 1980 |
A- |
Bellingham Mariners, Central Oregon Phillies, Eugene Emeralds, Grays Harbor Loggers, Medford A's, Salem Senators, Victoria Mussels, Walla Walla Padres |
| 1979 |
A- |
Bellingham Mariners, Central Oregon Phillies, Eugene Emeralds, Grays Harbor Loggers, Medford A's, Salem Senators, Victoria Mussels, Walla Walla Padres |
| 1978 |
A- |
Bellingham Mariners, Bend Timber Hawks, Boise Buckskins, Eugene Emeralds, Grays Harbor Loggers, Salem Senators, Victoria Mussels, Walla Walla Padres |
| 1977 |
A- |
Bellingham Mariners, Eugene Emeralds, Grays Harbor Loggers, Portland Mavericks, Salem Senators, Walla Walla Padres |
| 1976 |
A- |
Bellingham Dodgers, Boise A's, Eugene Emeralds, Grays Harbor Ports, Portland Mavericks, Seattle Rainiers, Walla Walla Padres |
| 1975 |
A- |
Bellingham Dodgers, Boise A's, Eugene Emeralds, Portland Mavericks, Seattle Rainiers, Walla Walla Padres |
| 1974 |
A- |
Bellingham Dodgers, Eugene Emeralds, Lewiston Broncs, New Westminster Frasers, Portland Mavericks, Seattle Rainiers, Tri-City Ports, Walla Walla Padres |
| 1973 |
A- |
Bellingham Dodgers, Lewiston Broncs, Portland Mavericks, Seattle Rainiers, Tri-City Triplets, Walla Walla Padres |
| 1972 |
A- |
Coos Bay-North Bend A's, Lewiston Broncs, Seattle Rainiers, Spokane Indians, Tri-City Padres, Walla Walla Islanders |
| 1971 |
A- |
Bend Rainbows, Coos Bay-North Bend A's, Lewiston Broncs, Medford Dodgers, Tri-City Padres, Walla Walla Phillies |
| 1970 |
A- |
Bend Rainbows, Coos Bay-North Bend A's, Lewiston Broncs, Medford Dodgers, Tri-City Padres, Walla Walla Phillies |
| 1969 |
A- |
Lewiston Broncs, Rogue Valley Dodgers, Tri-City A's, Walla Walla Bears |
| 1968 |
A- |
Eugene Emeralds, Lewiston Broncs, Medford Giants, Tri-City Atoms |
| 1967 |
A- |
Eugene Emeralds, Lewiston Broncs, Medford Giants, Tri-City Atoms |
| 1966 |
A- |
Eugene Emeralds, Lewiston Broncs, Tri-City Atoms, Yakima Braves |
| 1965 |
A |
Eugene Emeralds, Lewiston Broncs, Salem Dodgers, Tri-City Atoms, Wenatchee Chiefs, Yakima Braves |
| 1964 |
A |
Eugene Emeralds, Lewiston Broncs, Salem Dodgers, Tri-City Angels, Wenatchee Chiefs, Yakima Braves |
| 1963 |
A |
Eugene Emeralds, Lewiston Broncs, Salem Dodgers, Tri-City Angels, Wenatchee Chiefs, Yakima Braves |
| 1962 |
B |
Eugene Emeralds, Lewiston Broncs, Salem Dodgers, Tri-City Braves, Wenatchee Chiefs, Yakima Braves |
| 1961 |
B |
Eugene Emeralds, Lewiston Broncs, Salem Dodgers, Tri-City Atoms, Wenatchee Chiefs, Yakima Braves |
| 1960 |
B |
Eugene Emeralds, Lewiston Broncs, Salem Senators, Tri-City Braves, Wenatchee Chiefs, Yakima Braves |
| 1959 |
B |
Eugene Emeralds, Lewiston Broncs, Salem Senators, Tri-City Braves, Wenatchee Chiefs, Yakima Braves |
| 1958 |
B |
Eugene Emeralds, Lewiston Broncs, Salem Senators, Tri-City Braves, Wenatchee Chiefs, Yakima Braves |
| 1957 |
B |
Eugene Emeralds, Lewiston Broncs, Salem Senators, Tri-City Braves, Wenatchee Chiefs, Yakima Bears |
| 1956 |
B |
Eugene Emeralds, Lewiston Broncs, Salem Senators, Spokane Indians, Tri-City Braves, Wenatchee Chiefs, Yakima Bears |
| 1955 |
B |
Eugene Emeralds, Lewiston Broncs, Salem Senators, Spokane Indians, Tri-City Braves, Wenatchee Chiefs, Yakima Bears |
| 1947 |
Non |
|