It is also one of eight constituencies in the South Wales Central electoral region, which elects four additional members, in addition to eight constituency members, to produce a degree of proportional representation for the region as a whole.

In general elections for the Senedd, each voter has two votes.

The first vote may be used to vote for a candidate to become the Member of the Senedd for the voter's constituency, elected by the first past the post system.

Additional member seats are allocated from the lists by the d'Hondt method, with constituency results being taken into account in the allocation.

Note: The Electoral Commission record the UKIP regional vote here as 73.