Dominion Day is or was a commemoration day of the granting of national status in various Commonwealth countries.

Canada

Dominion Day () was the original Anglophone name of the holiday that commemorated the formation of the Dominion of Canada on 1 July 1867. The holiday was renamed Canada Day (Fête du Canada) on 27 October 1982.

From the 1960s into the 1980s, Dominion Day was the date the Miss Dominion of Canada beauty pageant, held at Niagara Falls, Ontario, to select the Canadian representative for the major international beauty pageants (Miss Universe, Miss World, Miss International, and Queen of the Pacific).

New Zealand

Dominion Day is the name given to 26 September, the anniversary of the day New Zealand was granted dominion status within the British Empire in 1907. No longer a statutory (bank) holiday, the only current official observance of the day is as a Provincial Anniversary Day in South Canterbury. There is support in some quarters for the day to be revived as an alternative New Zealand Day, instead of renaming Waitangi Day, New Zealand's current national day.