Those on a lower plan will get a lower data limit. A customer with a 6GB limit will only have 4GB to use overseas if they've already burned through 2GB, for instance. If you are on legacy rate plans, Simple Choice North America, or T-Mobile ONE, you will receive up to a maximum of 5GB of 4G LTE unlimited talk, text, and data beginning November 12.
The reason for this downgrade in data availability, according to Engadget, is that T-Mobile needs to pay heavy roaming costs in these countries. "In order to prevent usage beyond the intent of the product, we implemented a limit on the amount of monthly 4G LTE data", T-Mobile wrote on its support site.
In case you are in a plan with data stash, which allows you to accumulate data, the data will not be usable in Canada or Mexico anymore.
If you are on a US high-speed plan with 4GB data or 6GB data per month, you will get only 2GB data when you are in these countries. Once the cap is reached, you will be switched to Simple Global speeds only.
On November 12, T-Mobile will be adjusting the initial Mobile without Borders offer so that customers will only have access to 5GB of LTE data when traveling overseas in Mexico or Canada.
After unveiling a new "Mobile Without Borders" deal in 2015 to all ONE and ONE Plus customers, you've been able to enjoy that oh so sweet LTE data overseas in Mexico and Canada. Still, it appears T-Mobile has some issues to work out, this time around being trouble with how much data its customers are using when roaming overseas. The change comes into effect on November 12, 2017.
Those on the 10GB unlimited data plan and have already exhausted their 2GB in the United States before crossing the border will have a limit of only 5GB in Mexico and Canada combined.
- John Legere, CEO of T-Mobile in 2015. After the users have exceeded 80% of the 5GB limit, they will be sent an alert message from T-Mobile.