The promotion, which SBC says could be worth up to $340 per customer, is the most aggressive attempt to date by a large local telephone company to lure customers away from cable. SBC's move comes a few weeks after it lowered the price of its high-speed Internet service to $14.95 per month for new subscribers in its 13-state region.

Executives with SBC, the second-largest U.S. telecommunications company, have said they see a two- to three-year window to grab customers as cable companies such as Comcast and Time Warner ramp up their voice services. SBC expects to roll out its own video services broadly next year.

Between cable companies' voice offerings and wireless telephone alternatives, SBC and the three other Baby Bells are expected to lose some 26 million consumer phone lines--about 28 percent of their total--over the next five years, according to Banc of America analyst David Barden.

Under SBC's offer, cable customers who send SBC a copy of their bill will qualify for credits on SBC's high-speed Internet service and EchoStar's Dish satellite programing. The promotions begin July 1 and are offered for a limited time. The high-speed Internet deal requires a one-year contract.