BreachCensus

T-Mobile USA, Inc.

United States of America

T-Mobile USA, Inc. is an organisation in Wisconsin. It appears on the Massachusetts Attorney General breach-notification register, the California Attorney General breach-notification register and the Wisconsin DATCP data breach list with 5 confirmed incidents; the most recent notice was filed on August 16, 2021.

Data as of September 6, 2026.

Confirmed incident

US-WI

Occurred
August 13, 2021
Disclosed
August 16, 2021

Timeline

  1. August 16, 2021
    Reported to regulator Regulator

    WI AG breach notification: an unknown number of Wisconsin residents affected

    source

Litigation

  • Possible litigation — multiple candidate dockets found, not yet resolved to a single case.
What a Wisconsin notice means

Governed by Wis. Stat. §134.98. No state agency must be notified. Affected individuals must be told within 45 days, and the national credit bureaus too when 1,000 or more people are notified; DATCP lists breaches reported to it or found to affect Wisconsin consumers.

Note: the count is Wisconsin residents only when published, not a total; many notices do not include one.

Wisconsin breach-notification register ↗

Confirmed incident

US-MA

Disclosed
February 22, 2021

Timeline

  1. February 22, 2021
    Reported to regulator Regulator

    MA AG breach notification: an unknown number of Massachusetts residents affected

    source

Litigation

  • Possible litigation — multiple candidate dockets found, not yet resolved to a single case.
What a Massachusetts notice means

Governed by M.G.L. c. 93H. Notice to the Attorney General is required for a breach affecting any number of Massachusetts residents' personal information -- the statute sets no minimum count.

Note: the count is Massachusetts residents only, not a total.

Massachusetts breach-notification register ↗

Confirmed incident

US-WI

Disclosed
November 22, 2019

Timeline

  1. November 22, 2019
    Reported to regulator Regulator

    WI AG breach notification: an unknown number of Wisconsin residents affected

    source

Litigation

  • Possible litigation — multiple candidate dockets found, not yet resolved to a single case.
Confirmed incident

US-WI

Occurred
August 20, 2018
Disclosed
August 23, 2018

Timeline

  1. August 23, 2018
    Reported to regulator Regulator

    WI AG breach notification: an unknown number of Wisconsin residents affected

    source
Confirmed incident

US-CA

Occurred
September 14, 2015
Disclosed
October 1, 2015

Timeline

  1. October 1, 2015
    Reported to regulator Regulator

    CA AG breach notification: an unknown number of California residents affected

    source
What a California notice means

Governed by Cal. Civ. Code §1798.82. A copy of the notification must be sent to the Attorney General when a single breach requires notifying more than 500 California residents.

Note: no affected-count is published on this register.

California breach-notification register ↗