Starting in 2005, HM awards the Provincial Junior B Championship to the winner of the Keystone Junior Hockey League. The League Champions receive the Baldy Northcott Trophy, and represent Manitoba at the Western Canadian Junior B Championship for the Keystone Cup.
For the first 19 years of the Keystone Cup era (1980-98), the MJBHL Champs entered Provincial playoffs only 4 times. In 1986, against the winner of the Manitoba Eastman Junior B Hockey League, and against the Brandon Junior B's in 1980 and 1981. And in 1983, the first official year of the Keystone Cup, the Manitoba Amateur Hockey Association held its own set of playoffs. MJBHL and teams province wide were involved.
During the summer of 2018, the five southern teams in the Keystone Junior Hockey League withdrew to form the Capital Region Junior Hockey League. The teams citing travel expenses and the amount of travel involved in getting to the northern teams for games.
- Manitoba Junior B Hockey Champions (Baldy Northcott Trophy)
- Western Canadian Junior B Hockey Champions (Keystone Cup)
- Keystone Junior Hockey League (2005-Present)
- Manitoba Junior B Hockey League (1975-04)
(During the Keystone Cup era (1980-04), MJBHL entered Provincial playoffs 10 times in 25 years)
- Northwest Junior Hockey League (1999-04)
- Manitoba Eastman Junior B Hockey League (1986)
- NorMan Junior Hockey League (1979)
Note: (XXXX-XX) reflect years involved in Provincial Championship