Post office staff have been unable to recover any mail from 114 PO boxes which melted when fire tore through the Opononi Four Square.
Sunday night's blaze destroyed the shop but the adjoining hotel was saved by a double firewall, firefighters and a patron armed with a garden hose.
NZ Post spokesman Michael Tull said none of the mail in the PO boxes had survived. However, all the mail in an adjacent street posting box was intact.
From yesterday, PO box holders with ID were able to collect their mail from the Omapere Foodmart.
Mr Tull said box holders awaiting a particular piece of correspondence could ask the sender if it could be re-sent. Box holders with specific issues could call the NZ Post service centre on 0800 501 501.
