Police are working to improve security at a quarter of all police stations after an audit into firearms storage.
Police Commissioner Mike Bush ordered the audit after the theft of 11 guns from Palmerston North police station in April.
It showed the storage of police guns was good or excellent at three-quarters of the 329 police stations audited.
But Deputy Commissioner John Tims said the rest, about 80 police stations, needed work to get them up to scratch.
"I think we have to accept that there's work to be done," Mr Tims said. "There's some improvements that we need to make.
"The good news, I guess, is that we have started that work, we've completed some of the improvements that were needed, and we'll continue to do so.
"We do need to get better in this space, and we accept that."
The audit also found that the storage of non-police firearms, like those handed in as part of the gun amnesty, was average, good or excellent at the majority of police stations.
But police would not reveal how many failed to reach that standard, citing security reasons.
Mr Tims said he could not provide the numbers on the storage of non-police weapons, but said people should have faith in how police run the buy-back scheme launched after gun laws were tightened in the wake of the Christchurch mosque attacks.
"What I can say is that we're not storing firearms at every station," he said.
"We're making sure that where firearms are being stored that they're at the appropriate level of storage and security.
"This audit, in my mind, supports and enhances the buyback."
Mr Tims said CCTV cameras and alarms were being added to many police stations as a result of the audit.
Police are also working to improve how they catalogue items that are handed in.