Background

Makerfield is a UK parliamentary constituency in Greater Manchester, covering the towns of Wigan, Leigh, and Ince. The seat was redrawn in the 2023 boundary review and includes former mining and manufacturing communities with a strong Labour tradition. Labour has held the seat or its predecessors continuously since 1935. At the 2024 general election, Labour's Josh Simons won with a majority of approximately 8,400 on a reduced swing, with Reform UK in second place on 31.8 per cent of the vote.

On 14 May 2026, Simons resigned the seat to allow Greater Manchester Mayor Andy Burnham to seek election to Parliament as a prerequisite for a Labour leadership contest . The NEC approved Burnham's candidacy on 15 May 2026 . Burnham won the by-election on 18 June 2026 with 24,927 votes, a 54.8 per cent share and a 9,231-vote majority over Reform UK's Rob Kenyon, on turnout up to 58.77 per cent; the Conservatives collapsed to fifth on 2.2 per cent, behind Rupert Lowe's Restore Britain.

The result inverted the usual by-election penalty: governing parties normally bleed support and turnout mid-term, but both rose in Makerfield, and Burnham outran the Survation projection that had put him three points ahead by roughly twenty. Four days later Keir Starmer resigned as Labour leader and prime minister, citing the PLP's private verdict, making the 18 June result the launchpad for Burnham's expected coronation as Starmer's successor.