1930-31 Thunder Bay Senior Playoffs

Final
Best of 3

Port Arthur beat Fort William 2 wins to none.

Final
Best of 3

Woodmen of the World beat Fort William East End 2 wins to none.

Final
2 games total goals

Port Arthur Aces beat Port Arthur West End 8 goals to 3.

Intermediate Final
2 games total goals

Woodmen of the World beat Port Arthur Aces 5 goals to 4.

Senior-Intermediate Final
Sudden death


 * March 6 Port Arthur 5 Woodmen of the World 1

Port Arthur advanced to the 1930-31 Western Canada Allan Cup Playoffs.