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This segment is also mirrored on the T-Mobile Data article.
T-Mobile USA operates more than 7,000 T-Mobile HotSpot locations for Wi-Fi Internet access, including airports, airline clubs of American, Delta, United, and US Airways, Starbucks coffeehouses, Kinko's, Borders Books and Music, Hyatt, Red Roof Inn. The Wi-Fi infrastructure was completely replaced when T-Mobile bought the Wireless ISP MobileStar.
If you have T-Mobile Total Internet, you have unlimited HotSpots access, However getting the username and password for HotSpot access is a big deal and long conversations with customer support. The Username for HotSpot access is your full 10 digit phone number and the initial password is last 4 digits of your social security number (SSN). It will ask you to change the password on initial login.
If you are a FlexPay customer and did not provide a SSN, the default password is set to '1234'.