NZ Post had already made up its mind about closing a Christchurch call centre, and showed no willingness to compromise, a union says.
The EPMU said the company was aiming to save $2 million by shutting the centre next year, with 64 jobs going.
NZ Post said five jobs would also go from Wellington, bringing the total to 69, but that 45 new jobs would be created at the national centre in Auckland.
The EPMU said despite being called to a meeting two or three weeks ago, there was not really a consultation for workers in Christchurch, and when they asked for a two week extension to the process, they got three and a half days.
Union organiser for postal workers Joe Gallagher said the whole thing had been disappointing.
"In our view, it wasn't really a consultation, they've showed no willingness to work with us to come up with any alternative solutions.
"It's been a very disrespectful process to the union to the point where they said 'if you can come up with $2 million of savings by 2 o'clock tomorrow, we'll talk to you'.
"That's not how New Zealand Post normally conducts its processes so I'd have to say hopefully this was a one off behaviour because I've been very disappointed with how it's been run."
The Christchurch centre will officially close on the 12 November, but a skeleton staff of 25 will be left in place to both smooth the transition, and help deal with the Christmas rush.
It will then completely close in February 2016.
NZ Post rejects claim
NZ Post said allegations the unions or staff were not dealt with properly were not right.
Paul Trotman the company's chief customer officer said union and staff feedback had been taken on board.
"We have made some adjustments to the process. We extended the consultation process by almost a week and we've adjusted the timelines and approach to the transition.
"So there has been some changes but I guess the concept of compromise is fairly relative and complicated."
Mr Trotman also denied EPMU claims that NZ Post was exaggerating the decline in mail volumes, and pulling numbers out of thin air.
He said the decline was no secret and was a global issue that every country was dealing with.