The 1975 Chatham Cup was the 48th annual nationwide knockout football competition in New Zealand. Early stages of the competition were run in three regions (northern, central, and southern), with the National League teams receiving a bye until the later stages of the competition. In all, 123 teams took part in the competition. Note: Different sources give different numberings for the rounds of the competition: some start round one with the beginning of the regional qualifications; others start numbering from the first national knock-out stage. The former numbering scheme is used in this article.