People have been advised to make plans around the strikes
People are being warned to plan around strikes due to be held at six Post Offices in Northern Ireland.
It's expected that Belfast's Bridge Street, Bangor Main Street and New Row in Coleraine will all close on Monday.
Custom House Street in Derry - Londonderry, Frances Street in Newtonards and Antrim's Castle Centre will also be affected.
It's down to a row over jobs, pensions and branch closures.
Michael Legg from the Consumer Council had this advice for customers:
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