The number of Cleveland Police officers is to be cut by 230 in an effort to meet a 20% cut in government funding.
Cleveland Police Authority said the force's officer establishment would reduce from 1,727 to 1,572 over the next 12 months.
Authority chair Dave McLuckie said a further 75 posts would be lost in the following year.
Plans have also been agreed to cut the number of Police Community Support Officers (PCSOs) from 197 to 182.
Mr McLuckie said cuts to frontline services could not be guaranteed beyond the coming year.
He said the authority had agreed to make savings of £12m in the next financial year alone.
Mr McLuckie said a deal last year to outsource some civilian posts to private firm Steria had so far resulted in savings of £7m.
A further £5m will be achieved through measures including savings on overtime, Bank Holiday staffing, reduction in staff posts in the police executive and authority and reduced expenditure on uniforms.
Mr McLuckie added: "We have consistently made clear our determination to do everything possible to protect frontline services and we have achieved that for the coming year.
"But I do not want anyone to be under the illusion that this is the end of the story. There are more cuts in government funding in coming years and delivering savings at the same time as protecting the frontline will become ever more difficult."
A Police Federation spokesman said: "If the police service is able to do all that the public expects of it, it will need the shackles of financial restraint urgently removed.
"A cut of 20% over the next four years will inevitably lead to a poorer service, increased crime rates and will seriously jeopardise public safety and the security of the nation."