Norfolk and Suffolk Police will be merging their support services to save at least £9.8m, it has been announced.
Eleven of the services including human resources, media and communications and estates and facilities, will be merged in the next four years.
The move will mean at least a £9.8m saving across both forces, a Norfolk Police spokesman said.
A study is under way to determine whether the forces' legal departments should be merged.
Assistant Chief Constable for collaboration Charlie Hall said: "Our priority is to re-design our support functions so that they can support both our individual frontline services and collaborated teams more efficiently, ensuring we can deliver the best possible service to our communities.
Job losses 'inevitable'
"We acknowledge the fact that, while there will be efficiency increases, it is inevitable that some jobs will be lost.
"We are committed to managing this as sensitively as possible through regular communication and engagement opportunities with staff."
The proposals to carry out the merger were approved by Suffolk Police Authority on Friday and Norfolk Police Authority on Monday.
Fleet, professional standards, learning and development, finance and insurance, procurement and stores, ICT, change and corporate services and performance will also be merged.
It has been confirmed the administration departments will be kept separate.