Agency post workers walked out unofficially at the Royal Mail sorting office in Birmingham after bosses failed to pay their Christmas wages on time.
Some 35 workers took wildcat action for an hour at the main office in Newtown when their regular weekly wages went unpaid.
Agency worker Royston Allcock said, “We should get our money on a weekly basis every Friday. This is my third week without wages. Some of us still do not know when we are going to get paid.
“I have a wife and four children and I was relying on the money to buy presents. People have done the work and need the money.”
Royal Mail bosses beat a hasty retreat, blaming “difficulties with the payroll”.