The government is proposing changing the deed of understanding it has with NZ Post to only require post to be delivered a minimum two days a week in urban areas and three days a week in rural areas.
The Ministry of Business Innovation and Employment said the deed was last reviewed in 2013. It had been scheduled for review in 2018 but that was extended to 2024.
The ministry said, since the last review, New Zealand's digital connectivity had significantly improved.
In 2002, about a billion mail items went through NZ Post in a year. In the last financial year, that was 187 million and it is expected to drop to 107 million by 2028.
The ministry is currently seeking submissions as part of a consultation process.
"The proposed changes ...are intended to allow NZ Post sufficient flexibility to achieve commercial sustainability while still responding to New Zealanders' ongoing need for mail.
"Given ongoing decline in the use of the mail service and the years since the last deed review, it is time to consider whether changes should be made to the deed to reflect New Zealanders' declining use of the mail network. Changes also need to be considered to allow the mail service to continue in a commercially sustainable way."
At present NZ Post is required to deliver mail three days a week in urban areas and five days in rural areas.
The ministry said the changes to the deed would not automatically mean a reduction in service because NZ Post would still be able to make operational decisions.
Other countries had undertaken similar reviews and reduced obligations, it said. Denmark no longer has a national postal provider.
MBIE said NZ Post had stopped delivering on Saturdays in June and had not delivered on Saturday in rural areas for eight years.
The proposal would also reduce the obligation to have at least 880 "points of presence" for NZ Post, of which are 240 manned outlets, to 500 initially with a possible step down to 400 over time.
MBIE said most of the current 880 service counters were inside other retail shops.
The reduced requirement would reflect the cost to NZ Post of maintaining a network of postal outlets - "we understand it currently overserves certain urban areas to reach this requirement".
The 880 minimum has not been changed since it was set in 1989.
"NZ Post has said that any change, if made as a result of a new minimum number, will not disproportionately impact rural areas compared to urban areas. We note rural customers can also access mail services directly from the rural delivery driver in their area. Changes would also not be implemented immediately following deed changes or without appropriate notice"
Earlier this year, NZ Post confirmed plans to have parcels and mail delivered by the same person, rather than a separate postie and courier driver, as part of wider changes that would reduce staffing by 750 roles over five years.
