U.S. Cellular will pay you $300 to switch carriers
U.S.Cellular is also offering unlimited data plans for new and existing customers in its LTE coverage area for just $40 a month. Right now, 58% of the operator's customers are blanketed with its 4G LTE signal, a number that U.S. Cellular says will rise to 90% by the end of this year.
If all of this appeals to you, if you do bring over two lines and activate a smartphone, the carrier will send you a prepaid MasterCard debit card charged up to $300. It's a nice piece of change for doing something that you might have been planning to do anyway.
source: U.SCellular via AndroidCentral