The parish originally covered only 748 acres (303 ha) according to the 1881 and 1891 censuses. It was expanded greatly in 1934, taking in 1,823 acres (738 ha) and about 1,000 people from the dissolved Langley Marish parish.
Wexham civil parish was divided under the Local Government Act 1972, with the southern part becoming part of Slough and the northern part becoming part of South Buckinghamshire district. The northern part now constitutes the civil parish of Wexham, with the southern part being a parish called Wexham Court. Wexham Court has a parish council with 11 members. The parish and some additional unparished territory form the three-member Slough Borough Councilward of Wexham Lea. See Slough local elections for links to recent Borough election results.