Some 110 post workers in the CWU union walked out for three days last week in Bridgwater, Somerset.
They are out against job cuts, allegations of bullying management, and to demand £800 owed to each worker by management.
Shop steward Dave Chapple told Socialist Worker, “This is a major dispute for Bridgwater, solidarity is essential to win.
“The picket line has been solid over the days, with 50-60 workers, which must worry Royal Mail.
“We also need local strikes to break out around the country. Plymouth is also balloting members to strike.”
Another reason for the strike is Royal Mail’s failure to suspend a manager over allegedly opening a worker’s mail.