The ceremonial county of Berkshire currently comprises the unitary authorities of Bracknell Forest, Reading, Slough, West Berkshire, Windsor and Maidenhead and Wokingham. From 2024, it has returned nine MPs to the UK Parliament, including one which is shared with the county of Surrey.
As a result of the local government reorganisation introduced by the Local Government Act 1972, which came into effect on 1 April 1974, the boundaries of the historic/administrative county were substantially altered. Northern parts of the county were transferred to Oxfordshire while southernmost parts of Buckinghamshire, including the Borough of Slough, were added. This was reflected in the following redistribution of parliamentary seats which came into effect for the 1983 general election.
The table below shows the number of MPs representing Berkshire at each major redistribution of seats affecting the county.