Kim Leadbeater has been selected as the Labour candidate for the by-election in the West Yorkshire constituency previously represented by her sister.
The by-election was triggered after Tracy Brabin had to quit Westminster following her election as the first mayor of West Yorkshire.
The writ for the by-election was moved in the Commons by Labour on Thursday, with the party saying polling day will take place on July 1.
Labour is defending a majority of 3,525 over the Tories from the 2019 general election and Sir Keir Starmer’s party will be desperate to avoid losing another northern seat.
The party lost Hartlepool in a by-election on May 6 as another brick in the “red wall” of northern seats crumbled, with Ryan Stephenson hoping for a repeat performance as the Tory candidate in Batley and Spen.
Campaigning in Batley and Spen could be complicated by coronavirus, with Kirklees one of the areas where people have been encouraged to “minimise travel” due to the spread of the Indian variant.