The Rhode Island health insurance commissioner has approved rate increases of about 8 percent for Blue Cross and UnitedHealthcare, which will result in total premium increases of roughly $75 million.

But that is $15 million to $20 million less than the increase that the insurers requested, according to Commissioner Christopher F. Koller.

Blue Cross Blue Shield of Rhode Island had sought an increase of 9.4 percent. The state approved 8.1 percent.

UnitedHealthcare of New England and UnitedHealthcare Insurance Co. had sought an 11-percent increase. The state approved 8 percent.

The rates, which take effect Oct. 1, are for large group plans — employers with more than 50 workers. Small group plans will undergo a similar rate-increase review this summer.

This year’s review was the first under a new process mandated by state law that requires that affordability be one of the factors considered in setting rates. In the past, basically only the financial health of the insurance company was considered. That would allow companies to build up large reserves without regard to whether those reserves were needed or were making the rates too expensive.

Regulators reviewed three elements that go into calculating rate increases: how much money the company needs to bolster its reserves; how much it needs to pay increased administrative costs; and how much it needs to pay increased costs of covered medical treatment.

Koller approved the administrative cost increases as requested, although he attached conditions to United’s. The administrative cost increase for Blue Cross is 11.5 percent. The increase for United is 17.7 percent. As a condition of that increase, United is required to take steps to ensure that it treats medical providers fairly and that it contributes to improving the quality, accessibility and affordability of the state’s health-care system.

Koller made the biggest reduction in requested increases for the amount the companies will contribute to their reserves. Insurance companies maintain reserves to cover unexpected costs, such as those brought on by a catastrophe.

United had sought a 3.2-percent increase, but Koller cut that to 1 percent. He similarly cut Blue Cross’s 2.35-percent request to 1.35 percent.

“Both plans have more than adequate reserves,” he said in an interview.

Koller also made cuts in the increases each company requested for medical treatment.

Blue Cross had requested 9.4 percent; he approved 9.1 percent. United had requested 10.7 percent; he approved 9.9 percent.

Koller said his cuts were driven primarily by concerns he had in the increases each insurer sought for hospital stays.

Each insurer had to submit information about increases in four areas related to medical treatment: inpatient hospital care; outpatient hospital care; physician services; and pharmacy coverage.

The increases for inpatient care were out of proportion with the increases for physician services, Koller said. United had sought a 14.8-percent increase in inpatient care and a 7.9-percent increase in physician services. Blue Cross’s numbers were 9.6 percent for inpatients and 9.2 percent for physicians.

While state law dictated that the new review process take affordability into account, the process has had other benefits, Koller said.

A public review gives customers more information about how their insurer and its competitors operate and leads to greater public accountability, he said. It also promotes consistent treatment for each insurance company.

Koller said the experience of using the new system for the large-group rates will help streamline the process this summer for small groups. Next year, both groups will be dealt with at the same time, beginning in March. United and Blue Cross also will undergo the review for small groups.

Tufts Health Plan, which recently filed for a license to return to the Rhode Island insurance market, will not take place in the new rate-setting process until next year, if its license is granted.

pparker@projo.com