Workers at Christchurch's New Zealand Post contact centre are devastated to learn their jobs soon won't exist.

The call centre will close its doors on 69 staff next February, after scaling down begins in November.

Forty-five jobs will be offered to Christchurch staff in Auckland, while 27 will be lost completely.

The company's struggled with declining mail volumes, cutting once daily postal services to just three days a week.

EPMU organiser Joe Gallagher said the decision's just a slap in the face, and workers are feeling cheated by the process.

"Why couldn't we have had a sensible discussion about retaining a call centre in Christchurch? It's a real kick in the guts for these people that have supported New Zealand Post through the earthquake."

"The reality is that most of these people won't be able to afford to move in to the housing market. Not only do they live in a very tough environment in Christchurch, but everyone can see that the housing market's out of control in Auckland."

But New Zealand Post's Chief Customer officer Paul Trotman insisted the decision was not made lightly, and the company is left with only a few options and needs to move all staff to the same city.

"This is really tough for workers and it's a really hard decision to make," Trotman said, "but we have an obligation to maintain a commercially sustainable business and unfortunately this is one of the many changes that we're having to make to enable that."