T-Mobile has reached a new milestone in the war on spam calls and texts by establishing STIR / SHAKEN support with all major US networks. This will go a long way towards preventing scammers from circumventing anti-spam methods. and blocking calls by falsifying caller ID information. T-Mobile is the first major wireless provider to meet the targets set by the TRACED Act before the June 30 deadline required by the FCC.

Scammers notoriously use number spoofing to hide the true origin of a call or text message, sometimes even going as far as using an area code that matches the number they are contacting. The STIR / SHAKEN protocols were designed to make this tactic easily discoverable by attaching metadata at the point of entry of a call or text message and passing it through networks so that the destination can determine if the caller ID data is precise.

T-Mobile’s announcement highlights that 98% of all wireless customers in the US are now covered by STIR / SHAKEN through its network. In other words, if a call is coming from or going to a T-Mobile customer, it is very likely that it was authenticated and came from the number listed in the caller information. While calls may still originate from sources where they can be spoofed, they will not be authenticated and must be dialed as unverified numbers.

This is not T-Mobile’s first “first” in the war against number spoofing. The un-carrier has been leading the charge with the first operational call verification between two networks in early 2019, and then across three networks at the end of the same year. Integrations continued into 2020 and T-Mobile finally completed its goal with the Charter Communications Spectrum Voice integration.

The TRACED law will take effect on June 30, requiring that for all major networks the STIR / SHAKEN integration be linked with all other major networks. This leaves almost exactly three months for everyone to get down to business. Given that barriers to interconnection for each carrier have largely been reduced to a few fledgling networks and the completion of final tests, we can expect to see quite a few similar announcements before the June deadline.