Throughout its existence it elected one member to the House of Assembly and one to the Cape Provincial Council.

When the Union of South Africa was formed in 1910, the electoral qualifications in use in each pre-existing colony were kept in place.

The first challenge to the Cape Qualified Franchise came with the Women's Enfranchisement Act, 1930 and the Franchise Laws Amendment Act, 1931, which extended the vote to women and removed property qualifications for the white population only – non-white voters remained subject to the earlier restrictions.

In 1936, the Representation of Natives Act removed all black voters from the common electoral roll and introduced three "Native Representative Members", white MPs elected by the black voters of the province and meant to represent their interests in particular.

Its MP from 1974 to 1981, T. Aronson, joined fellow Port Elizabeth MP Myburgh Streicher’s South African Party on the UP’s dissolution in 1977, and unlike Streicher, retained his seat in that year’s general election.