The Department of Conservation (DOC) has decided not to increase fees for huts and camping grounds.

Tough economic times meant it was common sense to ensure people could continue to enjoy the outdoors without worrying about increased charges, Director-General of Conservation Al Morrison said.

Free access for under-18s to the nine "Great Walks" on public land would also be maintained, Morrison said.

"This summer, revenue from the recreation facilities is holding up.

"New Zealanders are staying at home and enjoying camping and other outdoor experiences on their conservation land."

However, DOC was concerned some people were not paying their way.

Many fees were collected through honesty boxes and some people were abusing the system, Morrison said.

"Costs continue to increase, international visitor numbers are declining, and this means there are significant uncertainties around future revenue. When people use facilities without paying their fees, that puts extra pressure on, and makes it harder to hold fees.

"It is unfair to the majority who do pay," Morrison said.

DOC manages a network of 12,800 kilometres of tracks, 940 huts and 250 campgrounds.