The Supreme Court's ban on gender-based variations in employer-paid retirement plans will have little immediate impact on the insurance industry as a whole and will not affect premiums for auto or life insurance purchased by individuals, industry officials said yesterday.

It "does not revolutionize the business of insurance," Richard Schweiker, president of the American Council of Life Insurance, said at a news conference here.

Representatives of Geico, State Farm, the United Services insurance group and other insurance companies said the narrow focus of the court's ruling limits its impact to a small percentage of group retirement policies and excludes the vast majority of fire, auto, life and disability insurance purchased by individuals in the open market.

Of far greater concern to the industry, they said, is the potential impact of legislation pending in Congress that would ban gender-based discrimination in all the fields of insurance the Supreme Court did not deal with.

Senate Commerce Committee Chairman Bob Packwood (R-Ore.), sponsor of the bill, said the decision "takes care of only part of the problem, making the need for legislation to bar discrimination based on sex even more important. It's now up to Congress to make nondiscrimination on the basis of gender the standard for all insurance, for all people."

The Supreme Court ruled 5 to 4 that federal civil rights laws ban employer-paid retirement plans in which women receive less than men each month. Many plans pay women less each month because they live longer than men, on the average, and therefore may receive the same total amount over time. These plans must be invalidated because "an individual woman may not be paid lower monthly benefits simply because women as a class live longer than men," Justice Thurgood Marshall wrote.

But the court made clear that the burden of providing nondiscriminatory benefits lies with employers, not with the insurance companies who provide the coverage. And the court said its ruling did not apply to other kinds of insurance purchased on the open market.

Representatives of women's rights groups hailed the court's decision as a step toward their goal of eliminating all insurance differences based on gender. But insurance executives said that, on the contrary, it left intact the principle that sex-based differences are permissible in most insurance contracts.

According to insurance industry and Labor Department studies, as many as 26 million Americans are covered by retirement plans administered by insurance companies. Most of these plans--including the retirement plans of most Virginia, Maryland and District of Columbia government employes--already provide equal benefits for all retirees, based on wages and years of service rather than gender.

John Booth, chief actuary of the American Council of Life Insurance, said the number of female workers enrolled in retirement plans similar to the one struck down yesterday is probably less than 3 million. Jack Blaine, ACLI's counsel, said plans with payments varying according to gender constitute less than 10 percent of the retirement-policy market, and that in turn is a tiny fraction of the overall insurance business.

"Our golden apples are auto and individual life insurance," said a representative of State Farm, one of the nation's largest companies. "Group coverage is a drop in the bucket."

"The effect on a lot of companies like ours will be minimal," said Charles Giuffra, a spokesman for the Washington-based United Services Life Insurance Companies. "Only a few companies that specialize in writing variable rate annuities will be affected."

Penny Farthing, an attorney for the American Insurance Association, a trade group of about 150 property and casualty insurers, said there will be "very little impact, none, on the property and casualty insurance business. Auto insurance is the only line of casualty insurance written on the basis of gender, and that was not affected by this case."

Opinion appeared to be divided on whether the ruling would increase or diminish prospects for enactment of the nondiscrimination legislation pending in Congress.

The insurance industry, which argues that practices such as charging higher premiums for young male drivers than young females reflect sound business judgments based on statistical probabilities, took comfort in the court's specific exclusion of these practices from its ruling.

"This makes it very unlikely the legislation will go through," said George Bernstein, an attorney representing several companies. "The silliness and danger of it will be so apparent there is no chance of Congress making that mistake."