Blue Cross and Blue Shield of Maryland was given 90 days yesterday to refund $10.8 million in excess profits that it first was ordered to repay almost two years ago.

In a tersely worded order, the Maryland State Insurance Commission demanded that the insurance giant either pay the sum immediately or suffer interest penalties for each day that it keeps large corporate and government subscribers waiting.

On July 1, 1980, Insurance Commissioner Edward Birrane ordered the nonprofit insurer to return $10.8 million in excess profit the company earned in 1979. After litigation that delayed the payment was settled earlier this year, Blue Cross and Blue Shield claimed that it lacked sufficient reserves to pay the refund.

At a hearing on June 15, Assistant Insurance Commissioner Thomas P. Raimondi denied a request by the insurer that it be excused from paying the refund. After the hearing, Raimondi said he was "particularly upset" that Blue Cross felt it had enough money to inject $5 million into a financially troubled health maintenance organization it bought last March but claimed to lack sufficient reserves to pay the refund.

Blue Cross and Blue Shield officials refused to comment yesterday on the order. They also refused to comment on their next course of action. Insurance commission officials believe the insurance giant will challenge the latest order in Baltimore City Court.

If it is forced to pay the refund, Blue Cross has stated that it will request a rate hike. Insurance commission officials already have said that no rate hike based on the refund will be granted.

Before yesterday's order, there had been speculation that Blue Cross and Blue Shield might be forced to refund approximately $3.5 million it has earned since 1979 by investing the excess profits.

As nonprofit organizations, Blue Cross and Blue Shield are not permitted to retain surpluses. One of the issues surrounding this controversy is what level of contingency reserves the insurer needs to guarantee safe operations.

Since 1979, combined Blue Cross and Blue Shield contingency reserves have fallen from $90 million to $80 million. Blue Cross claims that these reserves should not be depleted further through payment of the refund.