The chief constable has made his decision on the future of the full-time police reserve which is expected to be ratified by his most senior officers.
The full-time reserve has faced an uncertain future
It is thought that while there will be redundancies, several hundred officers will be retained.
Hugh Orde is due to officially announce his decision at a private meeting of the Policing Board on Thursday.
The full-time reserve has faced an uncertain future since the publication of the Patten Report on police reform in Northern Ireland in 1999.
Opinion has been split between nationalists and unionists over its future.
The Patten Commission recommended its disbandment, but DUP representatives told Mr Orde at a meeting on Monday that the PSNI could not afford to lose so many officers.
Almost 1,500 reserve officers had been waiting to hear the chief constable's decision.
Mr Orde will tell the Policing Board his decision on Thursday
As Mr Orde meets the Board, his deputy Paul Leighton will brief the Federation and the Superintendents Association.
On Wednesday, the Police Federation agreed a severance deal for its members in the full-time police reserve.
Terry Spence, federation general secretary, said it was the best deal they could have got.
He added that although he would like to see the chief constable recommend the full retention of the reserve, he realised Hugh Orde would recommend that a number of officers be made redundant.
"We met with the Northern Ireland Office today - these have been very difficult negotiations which have been going on for some 18 months."
He added: "It may not suit every single individual officer, in the way in which we hoped it would, but generally we believe the majority of our officers will be satisfied with what we have negotiated on their behalf.
"A significant number of officers will have an enhancement to their current pension... some officers will have a lump sum to the equivalent of £100,000.
"Of course, subsequent to that, at age 50, they would also have their commutation lump sum."
He added: "I haven't got any particular costings. Some people have mooted that it could be £100m-plus. I haven't seen the overall costings for it."
The Patten Report planned a "peace-time" service of 7,500 regular officers and 2,500 part-timers.
The review of policing in Northern Ireland by former Hong Kong Governor Chris Patten was one of the key elements of the 1998 Good Friday Agreement.