Reform UK has won the Southey ward by-election in Sheffield, with Labour finishing second. The result reinforces Reform’s recent strength in the ward and gives the party another councillor on Sheffield City Council.

The contest filled a vacancy created by the resignation of former Labour and then independent councillor Gareth Slater. It followed Reform’s victory in Southey at the May 2026 local elections, when the party’s Yvonne Sykes won 2,157 votes to Labour candidate Jayne Dunn’s 1,059.