The Devon and Cornwall Police Authority has approved plans for a 2% rise in its share of the council tax bill.
Chief Constable Stephen Otter said it would allow it to make planned cuts but maintain its service.
But it means about 700 police officers will still be cut from the force over four years.
The Police Federation said it feared more jobs could be at risk because the authority decided on a 2% rise rather than higher alternatives.
The authority could have increased its share of the council tax bill to 3.94%.
Nigel Rabbits, from the federation, said he understood there were tough economic times but a rise in council tax might have saved more officers.
Chief Constable Stephen Otter said: "It was a really difficult decision. We still have to make 20% cuts but effectively it will cost £3 a year for a Band D taxpayer."
The authority decided to reject a government grant which would have frozen its share of the council tax bill after concerns it would affect the service in years to come when the money was not available.
Over four years the authority has to make £47m of savings.