Massachusetts Governor Deval Patrick plans to recommend sweeping reforms in health care benefits for retired state and municipal employees, changes that are estimated to save up to $20 billion over the next 30 years.

The recommendations stem from a report due to be released Friday, January 11th by a special commission that studied the soaring costs of retiree health care in Massachusetts.

An administration official familiar with the report said it calls for raising the minimum years of service an employee must have before being vested in the retiree health care system from the current 10 years to 20 years.

The minimum eligibility age would also rise from 55 to 60 for most workers.

The changes would not affect any current retirees.