There are generally two types of campsites solutions: the DOC campsites and the private ones.
The DOC (Department Of Conservation) is the “public service department of New Zealand charged with the conservation of New Zealand’s natural and historical heritage“. Among the other activities, they managed several campsites all around New Zealand.
The DOC campsites tend to be cheap, basic and often in more remote locations. All these make the DOC campsites the perfect solution for backpackers!
The DOC usually need to be booked in advance but it is not always the case. In some DOC campsites there is no running water or kitchen facilities.
Check the map for all DOC campsites
Private campsites tend to be more equipped. They normally have a common area, kitchen facilities and shared toilets with running water. They can be even cheaper than DOC campsites and they are the perfect solution in a rainy day (remember…it is New Zealand). Even in this case it is better booking in advance.
We stayed in several campsites but we quite like the Kiwicamp in Rotorua. It was free, clean and shower cost 2$. The only downside is that you need to buy the KiwiCash Digital Key beforehand.
Check the map for Kiwicamp.