School admissions workers at Coventry Council are set to take indefinite strike action from next Monday.
They are fighting against sweeping changes to pay and conditions imposed last June on thousands of council workers.
Some staff - including refuse collectors - lost as much as £9,000 a year.
Along with workers who take cash payments over the counter - including council tax payments and parking fines and street cleaners - they voted 100 percent for action.
The payments workers and street cleaners are due to join the strike at a later date.
To send messages of support go to www.coventryunison.co.uk