More than 600 members of staff serving in the prison officer and governor grades, who are aged 50 or over, will be eligible to apply for the scheme.
The payments they receive will depend on the length of time in the job and individual circumstances.
But officials have given the example of what can be expected by an officer with 40 years' service and a salary of £37,000.
The officer's pre-tax package would total £120,250.
This includes a tax-free lump sum of £55,500, a compensation lump sum of £18,500 (before tax), compensation in lieu of notice £18,500 (before tax), and an additional payment of £27,750 (before tax).
The officer would also receive an annual pension of £18,500, which would be subject to tax.
Those staff opting for the scheme will begin to leave the Service from next spring.
In this very challenging economic environment, this is by far the best package the service can offer.
NIPS Director General Colin McConnell
The prison service is planning to recruit 400 new staff which will be introduced by 2012.
A different uniform is likely to be introduced and they will be known as custody officers and more highly skilled offenders' supervisors.
Justice Minister David Ford said the staffing levels have to be addressed to reform the Prison Service.
"The publication of this scheme underlines my commitment to fundamental transformation of the Northern Ireland Prison Service," Mr Ford said.
"As the programme of reform gathers pace over the next six months we should never forget the commitment and sacrifice shown by Prison Service staff," he added.
The scheme will cost £60m over the next two years but is expected to generate savings of £180m over the next 10 years.
"The publication of the scheme allows our officer and governor grades to make an informed decision about whether or not they want to be a part of the new and transformed Northern Ireland Prison Service or whether they wish to leave to pursue other interests," NIPS Director General Colin McConnell said.
"How we work, and the way in which we work, will change as we move towards becoming a modern, effective and efficient Prison Service with reducing the risk of reoffending at our core.
"The Exit Scheme is the catalyst for this transformation and will pave the way for a new business operating model to be launched next April," Mr McConnell added.
There has been criticism of the new scheme from the Prison Officers Association.
POA chairman Finlay Spratt said: "The officers of the future will still have to maintain control and discipline within the establishment."
"I think they are going to decimate the prison service, and if you think it's bad in the prison service now I think it is going to get worse."
Sinn Féin Vice Chair of the Justice Committee, Raymond McCartney, said: "There has not been open recruitment in the prison service since 1994 but the problems highlighted in many recent reports persist, highlighting the need for transformation, reform and modernistaion.
"This can only come about with new staff and the exit of old staff and their old habits."
But DUP Justice Committee member Jim Wells said the redundancy scheme should remain voluntary and experience of older Prison Service staff should not be disregarded.
"Whilst the cost of keeping a prisoner in Northern Ireland has been rightly pointed to as being well above that in the rest of the United Kingdom it is important that we do not leave the service without sufficient experienced personnel for the future," he said.
Prison Service management have met with the Prison Officers Association and the Prison Governors Association to brief them on the details of the scheme.
Depending on the uptake, the service may launch a second Voluntary Early Severance Scheme early next year for staff under 50.