The Western Australian Legislative Assembly is elected from 59 single-member electoral districts. These districts are often referred to as electorates or seats.
The Electoral Distribution Act 1947 requires regular review of electoral boundaries, in order to keep the relative size of electorates within certain limits. Electoral boundaries are determined by the Western Australian Electoral Commission. Electoral districts are subdivisions of electoral regions for the Legislative Council and have approximately an equal number of electors. The last electoral redistribution was completed in November 2015; it applied in the 2017 state election.