Cricket Wireless said the Lumia 640, which goes on sale May 15, will cost $129.99.
Early buyers of the phone will be rewarded with a one-year subscription to Office 365 Personal for use on the phone as well as on a tablet and on a PC.
The phone also offers 1TB of OneDrive storage for a period of one year, and 60 minutes of free Skype Unlimited Worldwide calling each month. The phone has a 5-inch HD screen, 8-megapixel camera, LTE, Bluetooth, WiFi, and GPS.
The Lumia 640 will ship with Windows 8.1, but can be upgraded to Windows 10 Mobile later this year. Cricket does not require contracts.