The cost of calling an ambulance for medical reasons is set to rise by $4 because of an increasing demand for St John's services.
St John's part charges in Northland will increase from $61 to $65 on April 1.
The graduated price increase will see the cost rise to $75 in 2013 and $88 in 2014.
St John Northland operations manager Tony Devanney said they had been operating on a reduced price for so long and he was hesitant to see the price rise.
However, he said St John was operating in a deficit. St John was a charity that was struggling to meet costs.