Rural Women New Zealand national president Sandra Matthews said the service cuts were a step backwards.
"They will make life harder for rural people who already face longer travel times, reduced access to services and unreliable digital connectivity."
Under the new arrangements, rural mail delivery will be reduced from five days a week to three and the number of postal outlets will drop from 880 to 500 and then to 400 over four years.
There will also be an increase in communal collection points over individual mailboxes.
"Rural New Zealanders rely heavily on postal services, not just for mail but for medication, paying bills, receiving essential deliveries and maintaining business operations.
"For many, frequent, accessible post services are a necessity", Ms Matthews said.
"Our rural communities are made up of hundreds of small businesses integral to the success of our main export earners, primary industries and tourism.
"The food and fibre sector alone makes up 10.5% of our GDP.
"These changes may reduce some costs to NZ Post, but they certainly won’t help increase productivity or maintain the viability of our regional communities.
"While we acknowledge the commitment that no rural retail service point closures will take place in the first year ... over the longer-term forcing people to travel long distances to access a post outlet or shared mail hub creates a significant barrier.
"This is a particular problem for older and more isolated rural residents, and makes doing business in rural areas even harder," Ms Matthews said.
RWNZ also noted that NZ Post, as a state-owned enterprise, was obligated under the State-Owned Enterprises Act to conduct with a sense of social responsibility by having regard to the interests of the communities in which it operated.
"Where is the social responsibility in decisions that isolate rural New Zealanders, strip away essential services and ignore the unique challenges these communities face?"
RWNZ is calling on the government to engage in dialogue with rural communities over how the most negative impacts of these changes can be mitigated and suggests dispute mechanisms could be instituted for affected communities.
"We also want to see a geographic criterion in NZ Post’s Deed of Understanding to protect access in rural and remote areas, a review of NZ Post’s operating model to identify more equitable service options and for NZ Post to be upfront about the post outlets in rural areas it plans on closing," Ms Matthews said.
