"Even after you sign up, you will receive a bill for your first month's service within a few days, but you will not receive the promised gift card to buyout your previous provider for almost eight to 10 weeks after you turn in your old devices."
Consider going with a prepaid plan
Verizon, AT&T, T-Mobile and Sprint (and most discount carriers) offer a variety of ridiculously inexpensive prepaid plans worth exploring when you’re eligible to re-up. They don’t come with as many perks as the two-year contracts (sorry, no free or discounted iPhone), but most feature unlimited talk and text. If you already have a device or don’t mind shelling out $100 for a lesser smartphone, this is an easy way to cut your bill way down without signing up for an annual contract.