"Equal access" came to 10 telephone exchanges in downtown Washington today.

Equal access allows telephone users to choose any long-distance service as their regular provider and make long-distance calls in the same way they now do with American Telephone & Telegraph Co.

In most of the country's telephone exchange areas where equal access has not been established, customers of MCI Communications Corp., GTE/Sprint and other AT&T competitors must punch in a series of access and identification numbers on their phone before placing their calls.

The process of equal access, mandated by the divestiture agreement that broke up the Bell System, gives long-distance companies the same quality of connection to the local telephone network that AT&T enjoys. Telephone office conversions are occurring nationwide on a neighborhood-by-neighborhood basis and are expected to be completed by the end of 1986.

Telephone exchanges in downtown Washington that can offer equal access today are 272, 347, 392, 393, 626, 628, 638, 662, 783 and 879.

Exchanges in Southwest Washington were converted in September.

Chesapeake & Potomac Telephone Co. notified customers in these exchange areas 90 days ago about the change, advising them that there will be no C&P charge for switching to another long-distance company within six months, but a $5 charge thereafter. Newcomers to Washington will not have to pay a fee for their initial choice of a primary long-distance company.

Customers who do not choose a long-distance company within six months will automatically stay with AT&T, a provision that has angered AT&T's competitors and some consumer groups. Their complaint is that an automatic "default" to AT&T in most equal-access areas around the country makes it too easy for customers not to make a choice about long-distance service, impeding the competition that was supposed to result from the AT&T breakup.

"C&P has set up a selection process in a way that is strongly biased toward AT&T," said Robert Krughoff, director of Washington-based Consumers' Checkbook, a nonprofit consumer group. "If customers just don't get around to making a choice, AT&T is the winner." Krughoff said in neighborhoods that were previously converted to equal access, the percentage of customers that made a selection within the six-month period ranged from 10 to 50 percent.

Northwestern Bell Telephone Co. is the only company with a selection program providing incentives to make a choice, he said. In Minneapolis, Northwestern Bell asked customers to fill out a ballot and then assigned them to a long-distance service if they did not make a choice. As a result, 70 percent of Minneapolis customers made a choice before the six-month deadline, Krughoff said.

Meanwhile, C&P Telephone Co. is making it easier for customers to read bills by consecutively numbering the pages, according to the company's consumer affairs manager, Rose Wheeler. Before the change, each section of the bill was numbered separately starting with a new page one.

C&P also is using logos at the top of each page to designate which portion of the phone bill is C&P's and which portion belongs to a long-distance company, she said. Since the breakup of the Bell System, C&P has been a billing agent for some long-distance and phone equipment companies.

Shading for subtotals of each type of service charge, toll calls and credits, and use of more simplified English also are new features, she said.