ACC are proposing halving the number of staff in Hastings from 67 to 33.
Consultation over the proposal, which could see 300 staff laid off around the country, began on Wednesday.
If the new structure proceeds, it takes effect from January 24 next year.
Chief Operating Officer Mike Tully said the new structure will create new roles in the company but will also see a large number of job cuts if it goes through.
"A significant number of new roles are being created across New Zealand. At the same time, there could be around 300 redundancies over the next 12 months, not accounting for natural attrition, or people taking up relocation opportunities. Overall, the number of people in our client service teams will remain at around 1800," Tully said.
"We're changing because our clients have told us we need to. They've told us to make it easier for them to interact with us; to simplify things, be more efficient and ensure our service is consistent. So, we're proposing changes to how our client service teams work, and the locations from where they provide particular types of support.
"All 25 existing ACC sites will remain open and we'll continue to offer face-to-face services for clients where it supports their recovery," Tully said.
Proposed structural changes will see new roles created in five hubs – Auckland, Hamilton, Wellington, Christchurch and Dunedin – to work with clients recovering from less severe injuries such as sprains, strains and fractures.
These types of injuries, which make up 94 per cent of claims, do not usually require face-to-face support.
Tully said the changes are all designed to provide a faster, more flexible service that gives clients more options on the amount of help they receive.
"Our intention is to also significantly reduce the 40 per cent of time our client-facing employees currently spend on administrative tasks, freeing up more time to work directly with those who need tailored care and recovery plans.
"We've been testing this new approach in Hamilton and Hawke's Bay over the past 18 months with more than 25,000 clients supported by 100 employees.
"We recognise all our client support people are impacted by these proposed changes and that this is a difficult time for them. We are being transparent and supportive throughout this process."
Employees affected by the proposed changes will be offered reassignment to an appropriate role in the same location if one is available, reassignment to a similar role in a different location if they are interested or, where this is not feasible, offered redundancy.
Tully says the changes are part of wider improvements all aimed at improving ACC's client experience and health outcomes.
"This is not a one-off change. Our intention is to continue improving and refining how we support our clients, especially through greater use of technology."