Staff at Ngā Taonga Sound and Vision have been told its Auckland and Christchurch offices will close, and there will be some redundancies at its Wellington base.
Originally the New Zealand Film Archive, it added RNZ's sound archive in 2012 and the TVNZ archive in 2014. It employs about 80 people nationwide.
The organisation confirmed this afternoon that it would centralise its collection in Lower Hutt, relocating its audio and visual collections from Auckland and Christchurch.
In a statement it said five jobs would be lost in the move.
Emma Kelly, a film researcher who campaigned against the restructure, said the changes meant valuable heritage material and expertise would be lost.
She said moving all the country's treasured audio and visual history to one place would be disastrous for many reasons.
"It will be very hard to move them properly. They won't have the right staff to move them properly. Not all the staff will be coming with the material so it's possible we will lose material."
"There is no magic digitisation fix. And once they're in Wellington and there's a natural disaster we've lost our cultural heritage."
Dr Kelly said the organisation needed to halt its plans.
It was possible people who had donated material to the archive in the past could ask for it back because they would not feel confident their material was safe, she said.
Ngā Taonga chief executive Rebecca Elvy said she believed the changes would keep the collections safe and access to them would not change.
She said the collections were being moved to a purpose-made archive facility at The Avalon in Lower Hutt, and the building is of a high standard of resilience to natural disasters.
Ms Elvy would not answer questions or give further comment on this morning's statement.