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T-Mobile offers nationwide mobile coverage for talk, text, and data, without a monthly contract, with plans starting at $50 per month. And right now, when you bring your device and old number to T-Mobile, you'll get up to a $400 prepaid Mastercard on them for making the switch.

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This deal applies to all T-Mobile plans, including Essentials, which means you don't have to spring for the most expensive Experience Beyond plan to get your gift card. However, if you do choose the cheaper Essentials option, you'll only qualify for a $300 gift card, which is still a great rebate. All T-Mobile phone plans include unlimited talk and text, but only the Experience More and Beyond plans offer unlimited data. The higher-tier plans also include a 5-year price guarantee, so you can lock in your current plan fee for long-term savings.

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To get your prepaid Mastercard, new T-Mobile customers must pick a plan and then download the T-Life app for a guided walkthrough on how to switch networks. Once you're all set up, you'll get a link to claim your $400 gift card. You'll have 30 days to claim, and delivery may take up to eight weeks. 

How I rated this deal 

Getting free money just for switching mobile carriers sounds like a deal that's too good to be true. But T-Mobile has made it a reality for anyone looking to move from Verizon or AT&T. With a simple 15-minute onboarding process, you can quickly and easily bring your old device and number to a new network. And get paid in the process. That's why I gave this deal a 4/5 Editor's rating.