Through rain, sleet and snow, the mail must go through...and apparently it has.

New Zealand Post is confident it has delivered all the items it received in time for Christmas.

Chief Operating Officer Mark Stewart said they cleared all the remaining parcels, mail and Christmas cards at depots last night, and only failed to deliver them if no-one was home to receive them.

He said they had thousands of couriers on the road and extended the hours at post shops, to allow people to pick up their packages if they weren't home when their package was delivered.