South Africa, Constitution 1996 (as amended in 2012), accessed 29 May 2019
46. COMPOSITION AND ELECTION
1. The National Assembly consists of no fewer than 350 and no more than 400 women and men elected as members in terms of an electoral system that -
a. is prescribed by national legislation;
b. is based on the national common voters roll;
c. provides for a minimum voting age of 18 years; and
d. results, in general, in proportional representation.
2. An Act of Parliament must provide a formula for determining the number of members of the National Assembly.
South Africa, Electoral Act 73 of 1998 (as amended in 2019), accessed 29 May 2019
Schedule 1A, Section 57A
2. The seats in the National Assembly must be filled as follows:
(a) One half of the seats from regional lists, submitted by the respective parties, with a fixed number of seats reserved for each region, as determined by the Commission, for every election of the Assembly, taking into account available scientifically based data in respect of voters and representations by interested parties.
(b) The other half of the seats from national lists submitted by the respective parties, or from regional lists where national lists were not submitted. […]
South Africa, Election Commission, Seat calculation: National Assembly and Provincial Legislatures, accessed 29 May 2019