Education staff at 48 prisons and youth offender institutions are set to vote on strike action in a row over low pay.
Around 500 University and College Union members will be balloted on the action from next week. The staff are calling for a pay rise that helps them meet the cost of living crisis.
Novus, their employer, has offered a two per cent rise for 2021/22 and three per cent for 2022/23, below the current RPI inflation of 12.3 per cent.
The UCU claimed that prison educators have seen their pay fall by more than 25 per cent since 2009.