State Insurance, New Zealand's biggest fire and general insurer, plans to lay off up to 245 staff and close more than 30 branches, including four Auckland offices.
Call centres in Hamilton and Tauranga will be closed.
The Hamilton centre employs 130 people and 75 jobs will be lost in Tauranga.
Thirty-one of 61
sales branches will shut and the number of call centres cut from five to three.
Many of the branch closures will hit smaller towns, including Greymouth and Westport, the firm's only branches on the West Coast.
Other centres to lose out will be Upper Hutt, Feilding, Hawera, Ashburton, Oamaru, Queenstown and Taupo.
When Australian general insurer NRMA bought State for $404 million, it said that State had to slash at least $10 million a year in costs.
Spokesman Shaun Hickey said it was not known if the planned restructure would meet that target.
The three remaining call centres will be broken into sales and service (Auckland), business support and broker business (Wellington) and claims processing (Christchurch).
Richard Wagstaff, national secretary for the Public Service Association - the largest union representing workers in the company - said there would clearly be job losses.
"The PSA will negotiate with State Insurance to ensure that the quality of services is not compromised."
"However quality service is only part of the equation. It is also important that our members have access to satisfying jobs and rewarding career structures," Mr Wagstaff said.
State employs 1400 people and underwrites 1.5 million policies for more than 700,000 customers.
- NZPA
