The postage of parcels bought online appears to have remained steady, despite the economic downturn.
New Zealand Post says this has helped offset a general decline in postal volumes.
Profit at NZ Post slipped by a fifth to $42.5 million in the six months to the end of December.
Domestic mail and postal volumes fell by 5.7%, with some 27 million fewer items being sent.
But chief executive Brian Roche says the number of parcels sent as a result of internet shopping appears to be holding up well.
He says broadband is very good in many ways, but it can't physically transport things. so they have to be delivered.
Mr Roche says NZ Post now service more households than before - with less volume but higher growth.
Total package volumes are expected to pick up again as economic conditions improve.