Contact T-Mobile customer service to pay your bill by calling 877-746-0909 or by dialing 611 from your T-Mobile wireless phone, as of 2015. The customer service phone line is open seven days a week from 6 a.m. to 10 p.m.
When you speak with a customer service representative for bill payment, there is a $5 fee added to your next phone bill, as of 2015.
Alternatively, you can choose to use the automated system when you call the customer service number to pay your T-Mobile bill. This method is available 24 hours a day, and there is no fee when using the automated system.