Federal women who retire, or who become eligible for retirement, after Dec. 1, 1982, will lose all or part of a benefit they can now get as the spouse or surviving spouse of a person entitled to a Social Security workers' benefit. That is a mouthful, but this is complicated stuff.

In 1977 Congress, in reaction to a Supreme Court decision that made non-dependent husbands and widowers eligible for Social Security spouses' benefits, enacted an offset provision. It is designed to reduce the Social Security spouses' benefit of a federal worker by the amount of his or her own pension.

To protect thousands of women who would have lost the spouses' benefit entitlement immediately, Congress also added a "grandmother clause." It said women who qualified for their own federal pension by Dec. 1, 1982, would be excluded from offset.

Idea was to give them a five-year grace period to qualify for the Social Security benefit earned by their husband. That means women who retire or are eligible to retire from government by the Dec. 1, 1982, cutoff date will get the full Social Security benefit as the spouse of a worker insured under Social Security just as they would have before Congress changed the law.

U.S. workers (most of them women) who qualify by the Dec. 1, 1982, deadline will be allowed to get a Social Security benefit based on the earnings of their husbands under Social Security, in addition to the full amount of their own federal pension. Women who retire or become eligible to retire AFTER that 1982 cutoff will be subject to offset, just like men.

Offset is the reduction in the Social Security spouses' entitlemen benefit equal to the retirement benefit the U.S. woman worker gets for her own federal service. Most long-service feds will get a U.S. retirement benefit that is equal to or better than anything they would get as the spouse or surviving spouse of an individual covered under Social Security. For them, the offset law means they will not get that benefit. But they will get any Social Security benefit they earned themselves under Social Security.

Legislation, has been introduced to extend the deadline past the December 1982 cutoff. But unless and until any extension is granted, that is the cutoff date to watch and be aware of.