NEW YORK (TheStreet) -- Shares of Sprint (S) were falling 1% to $4.82 Tuesday after the wireless carrier announced a new promotion to offer lower monthly service plans to subscribers switching from Verizon (VZ) or AT&T (T) .
Under the promotion, current Verizon or AT&T subscribers who go to a Sprint store with a current bill will be offered a similar service plan at half the price they paid to the other carriers, before any monthly device costs. Sprint will also offer a gift card of up to $350 to those who switch to cover early termination fees from the other carriers.
Those who take Sprint's offer will have to either buy their phones at full price or choose to pay monthly payments on their phones, as the offer does not include subsidies for phones or two-year contracts.
T-Mobile (TMUS) customers are not eligible for the half-off promotion.