South West Hampshire was a proposed unitary authority area that was scheduled to be created in April 2028 in Hampshire, England, as part of ongoing local government reform. It would have been formed by a merger of the existing unitary authority of Southampton with the two-tier district of Eastleigh, as well as parts of the New Forest and Test Valley districts including Totton and Hythe. The first councillors would have been elected in May 2027, and the new authority would have assumed full powers in April 2028.

The area has a estimated population of 510,102.

Plans to create it were withdrawn in September 2026 and the 2027 election was cancelled.

Parishes The area would have the following parishes:

Allbrook Bishopstoke Botley Bursledon Chandler's Ford Chilworth Eastleigh Town Fair Oak and Horton Heath Fawley Hamble-le-Rice Hedge End (town) Hound Hythe and Dibden Marchwood Nursling and Rownhams Totton and Eling (town) Valley Park West End

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