Hundreds of Royal Mail workers in Kent have started a 24-hour strike in a dispute over pay, job security and working conditions.
Communication Workers Union (CWU) members at Maidstone, Chatham, Medway Valley, Sheerness and Faversham stopped work at 0400 BST.
The action, which is part of a national dispute, is expected to disrupt mail services in the ME postcode areas.
Royal Mail said declining mail volumes made structural change unavoidable.
A spokesman for CWU Kent Invicta branch said: "Postal workers in Kent are sick and tired of an inept management team running our business into the ground.
"Workers are busier than ever and being treated appallingly on a daily basis.
"The current round of cuts in jobs and services is unacceptable."