Activate refill minutes on a Straight Talk wireless cell phone by accessing the phone's Prepaid menu and selecting Add Airtime. After launching the browser on the phone, select Refill My Account. Alternatively, refill airtime at StraightTalk.com by clicking Refill Now under the Refill heading on the home page.
If using a prepaid Straight Talk card, enter the personal identification number found by scratching off the gray strip on the back of the card. As of 2015, call 877-430-2355 to refill minutes by phone.
Straight Talk also offers automatic refill via the Auto-Refill link under the Refill heading. Straight Talk sends a text both before and after the charge date.