The Reagan administration is expected to try to raise the retirement age next year for most federal workers and take another crack at putting a lid on government retiree cost-of-living raises.

Currently federal employes can retire at age 55 with 30 years of service and begin drawing immediate annuities that are equal to 56.25 percent of their average high-three-year salary. One option under discussion would be to raise the retirement age to 63, with a 3 percent annuity reduction for each year of retirement before that age. Other options are also being considered.

Raising the retirement age would save the government money by requiring employes to work longer (and pay 7 percent of salary into the civil service retirement fund) and draw benefits for a shorter time.

The idea could be politically popular with nonfeds because it would more closely coordinate the civil service retirement age with Social Security. Currently individuals must be age 65 before they begin drawing full Social Security benefits, although many people elect to take a reduced Social Security benefit at age 62.

Raising the retirement age for government workers could run into a snag in Congress, however, because it would also put pressure on senators and representatives to deliberalize their own retirement system. Members can now retire on immediate annuity after 20 years' service, which is equal to 10 terms in the House or three-plus terms in the Senate.

Administration officials, looking for ways to reduce the federal deficit, are also preparing to take another run at a legislative attempt to "cap" future cost-of-living raises for retirees. Congress this year tentatively approved a 4 percent ceiling on the next three cost-of-living adjustments (COLAs) for retirees. That would have saved an estimated $5 billion over the next three years.

But congressional conferees decided instead to limit COLAs to "younger" retirees -- those under age 62. That measure, which hits about 180,000 retired civilian government workers and about 800,000 military retirees, will save an estimated $113 million by the end of fiscal 1985 when the cap is supposed to be removed.

An administration official said the Office of Personnel Management is preparing a "load" of legislative proposals, some of which deal with federal retirement matters.

"But nothing has been finalized at OPM," he said. "It still must be run by [and approved by] a Cabinet committee at the White House before it becomes an administration proposal."

He did note, however, that "over half of all federal employes retire well before age 60 whereas in the private sector only 7 percent of the people retire before 60."

Any proposal to raise the government's retirement age could get a shot in the arm from the National Commission on Social Security Reform. That blue-ribbon panel meets and votes this week on recommendations it will make shortly to the president and Congress.

Although its recommendations are not final, the commission is almost certain to recommend that federal and postal workers hired in future be brought in under Social Security where the regular retirement age is 65.