Nearly 30 million fewer letters and parcels were sent by snail mail in the past year - but a more dramatic decline was prevented partly by bulk mailouts during the general election.
In its half-year report, New Zealand Post chairman Michael Cullen reported there was a 7 per cent drop in the volume of mail being sent within New Zealand.
Dr Margalit Toledano, senior lecturer in the Department of Management Communication at the University of Waikato, said social networking sites and online media had made communicating much easier and the convenience and the immediacy had pushed postaside.
"Even when I send a postcard, people are moved by it - they can't believe it. People just don't send postcards any more. Online is much easier and immediate and you can reach out to more people," she said.
"Geographical distance is not a problem any more ... you can send an email immediately."