Postal workers in Bridgewater, Somerset struck on Saturday 6 July in a dispute over job cuts and management bullying.
Communication Workers Union (CWU) rep Dave Chapple said the strike was “one of the best we’ve ever had”, with over 100 workers taking part.
Union reps have promised escalation if the dispute is not resolved.
In Peterborough, 170 postal workers held a wildcat strike following the suspension of a union rep.
There was also a strike at a delivery office in Plymouth. The CWU said members are fed up with increasing levels of bullying and harassment from bosses.
The strikes come in the context of government plans to privatise Royal Mail. A recent consultative ballot of CWU members returned overwhelming support for keeping Royal Mail in public hands, as well as for industrial action to stop the sell off and on ongoing industrial issues (including pensions) within Royal Mail.
The ballot returned a 96% vote against privatisation on a 74% turnout.