You can purchase up to six phones to get an additional six phones for free.
Brad's Deals Editor Michael,
Get a Samsung Galaxy S9 or Galaxy S9+ with a new line at T-Mobile, and you can take $720 off a second S9 or S9+ phone. If you purchase two Galaxy S9 phones, this deal will make the second phone free. For T-Mobile customers, this is the best deal we could find for two Galaxy S9 phones. This offer is open to new customers who open two lines of service, and existing customers who open at least one new line of service. The device credit will be applied to your bill each month, over the course of your 24-month plan. Shipping is free, and sales tax is charged in most states.