Andy Furey is the National Officer for Communication Workers Union, which represents staff working in Crown Post Offices.
He told ITV News: "A Welsh town like Holywell needs a Crown Post Office. If we lose it, this could be the death knell for the high street in Holywell."
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All calm and quiet overnight, but southern areas could be in for a surprise tomorrow!
Scottish people living in Wales have been giving ITV News their opinions about the Scottish referendum vote on Friday.
While the campaign trail in Scotland has hotted up today, in Wales businesses are keeping a close eye on tomorrow's decision.