Posties are concerned a new proposal could see fewer mail deliveries to homes and more postal hubs for people to collect their mail from instead.
The Post Workers Union says it is already happening in rural areas and fears it could creep into urban areas.
The National President of the Postal Workers Union John Maynard told AM on Thursday he has concerns about the proposal as it could lead to more mail being stolen.
"What has happened is these boxes are being vandalised. So we've had a case where two or three times now the boxes are found to be broken into and the people don't know actually what they've lost and they don't know whether they've lost important mail or parcels," Maynard told AM co-host Melissa Chan-Green.
When pressed by Chan-Green if there is any difference between someone stealing from the letterbox at your house, which also occurs, and at a hub, Maynard said people's personal letterbox is "much more secure".
"Although some (letterboxes) are broken into of course, we've seen that in one bank in particular, I think there were 46 boxes, a whole lot of them were broken into at once. It's much more secure when it comes to your individual house," he told AM.
Maynard believes the proposal is simply a cost-cutting measure and fears it could grow into urban areas which would see fewer mail deliveries to homes.
"The company (NZ Post) has had a subsidy from the Government, which is running out about now and the company is talking about moving from more of a service model to a commercial or corporate model," he said.
"We are concerned they are going to look at extending further to banks of boxes and not going to individual houses, not just in rural areas but also in urban areas."
The union will present a petition to a select committee on Thursday, opposing the proposal for more hubs and demanding they continue deliveries.
"Our submission to the Select Committee today is to ask that it's the people who have some voice in deciding the future of a postal system, not just some of the directors or senior managers," Maynard said.
Maynard will be asking the committee to allow Kiwis to have a voice in deciding the future of postal services.
"We're asking the select committee to actually ask the people so that people have a voice as mail volumes decline, what is the minimum standard of postal service that people would accept and that it would need to be subsidised by the Government, by the taxpayer," he said.
"We believe that people do want a minimum postal service of some standard and they're the questions that we want the people, the businesses, the community groups, the opportunity to tell a select committee, this is the sort of postal system we think is a minimum."
In a statement, a NZ Post spokesperson said they don't have an overarching strategy for delivery "hubs".
"Where new developments or properties request mail delivery we do consider a wide range of options depending on the circumstances, with community mailboxes being one option," they said.
"These scenarios are reasonably uncommon and typically unique to new rural developments, not existing delivery points. The Deed of Understanding allows up to 3 percent of mail delivery points to be served via counters or community mailboxes, and as of our last annual report that percentage was 1.56 percent.”
In response to Maynard saying that "hubs" would see more mail stolen, NZ Post said they don't have any evidence that this is the case.
"A locked box is typically more secure than an average letterbox (located on someone's property)."
Watch the full interview with John Maynard in the video above.
