To qualify for the ETF rebate, which is delivered as a Visa prepaid card, you'll have to keep your Sprint account in good standing for 45 days; register for the rebate before March 15, 2015; and allow up to 12 weeks for your card to arrive in the mail.
Sprint's deal doesn't offer any relief from taxes, surcharges, or other fees that always sneak into cell phone bills. This is purely about cutting your service plan cost in half, and nothing else. Sprint will, however, waive the activation charge as part of the deal.
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