Business leaders joined forces with consumer advocates today and attacked Chesapeake & Potomac Telephone's request to raise Virginia phone bills by $94.1 million a year.

The unusual coalition of phone customers urged the State Corporation Commission to turn down C&P's bid for higher rates and a state official urged giving the phone company only one-third of what it is asking.

Rather than boost bills, C&P ought to tighten its belt like everyone else, urged William G. Reynolds Jr., vice president of Reynolds Metals Co., one of the state's biggest industries.

The corporation commission began what is expected to be six days of hearings on whether C&P should get the full $94.1 million rate increase it is requesting, make do with the $66.5 million conditional increase awarded by the SCC last November or settle for less.

The utility asked for $133.5 million last August but later reduced its request by nearly $40 million. Since the $66.5 million already is being collected by C&P, any decision to trim that amount would force the utility to make refunds.

C&P officials have insisted they need the full $94.1 million to cover the costs of inflation and to be able to compete for funds in the investment market.

Basic C&P residential charges before the interim increase in November ranged from $5.81 at Big Island in Bedford County to $11.79 in Alexandria.

The basic charge for residential telephone service in the Richmond area went from $10.30 a month to $11.17 after the $66.5 million interim rate increase took effect. An award of the full $94.1 million would boost the charge to $11.46.

Reynolds, one of a half dozen public witnesses to testify, noted that Reynolds Metals and other industries are laying off workers, freezing wages and taking other drastic cost-cutting measures in the face of severely declining earnings.

"These are hard times for everyone and increasing profits cannot be expected to continue uninterrupted. Given this economic environment for Virginia, her people and her industries, the C&P's rate increase seems ill-timed," Reynolds said.

Dennis Gallagher, executive assistant for the Virginia Homebuilders Association, vigorously protested proposed C&P labor rates of $61.80 an hour for wiring new homes for telephone service.

"This is just going to further depress the housing industry," he said.

Douglas C. Roberts, an SCC staff attorney, noted that C&P was awarded a $35 million rate increase in 1980 and another of $77 million in 1981.

Assistant Attorney General Eric Page set $29.8 million as the maximum increase that should be granted the utility. This would be far short of the $66.5 million interim increase already awarded by the SCC and less than a third of what the phone company hopes to get.

A decision in the case is not expected until later this year.