The main opposition United Party slightly increased its share of the popular vote, but nevertheless saw its parliamentary representation considerably reduced.

The number of House of Assembly seats for White voters in South Africa had been increased from 150 to 160 by the Constitution Amendment Act of 1965.

The Progressive Party (PP) won the two seats representing coloured voters on the Cape Provincial Council, at an election in 1965.

[2] The South Africa Act 1909 had provided for a delimitation commission to define the boundaries for each electoral division, for general roll voters in the four provinces.

The Republican, Front and Conservative National groups were new right-wing parties, which had not contested previous general elections.

The Progressive Party barely kept its Houghton seat, held by Helen Suzman since her defection from the UP, winning by 117 votes.