T-Mobile USA

Disclosed Oct 1, 201510 years agoConfirmed

Official notice

What is known

People affected	Not stated in the sources we have
Disclosed	Oct 1, 2015
Happened	Sep 14, 2015
Attack	Not stated
Data exposed	Names, Social Security numbers, Government IDs, Payment cards
Sector	Telecom · US
Status	Confirmed

Sources

Source	Kind
California Attorney General breach notice: T-Mobile USAoag.ca.gov · Official notice	Official notice
Indiana Attorney General 2015 data breach report: T-Mobile USAin.gov · Official notice	Official notice
Maine Attorney General breach notice archive: T-Mobile USAmaine.gov · Official notice	Official notice

Notices filed

Where	Filed	People
California AGresidents of CA	Oct 1, 2015
Indiana AGresidents of IN	Oct 1, 2015	224,467
Maine AGresidents of ME	Oct 1, 2015	12,952

Other breaches at T-Mobile USA

Breach	Disclosed	Attack	Sector	Status	Affected
Disclosed Jan 19, 2023Jan 19, 20233 years agoHacking	Jan 19, 20233 years ago	Hacking	Telecom	Confirmed	Unknown
Disclosed Aug 24, 2021Aug 24, 20215 years agoHacking	Aug 24, 20215 years ago	Hacking	Telecom	Confirmed	Unknown
Disclosed Mar 10, 2020Mar 10, 20206 years ago	Mar 10, 20206 years ago	Not stated	Telecom	Confirmed	1,027

History of this record

2026-09-25 · data_types: [] to ["names","ssn","government-id","payment-card"] · backfill source
2026-09-25 · source: empty to https://www.in.gov/attorneygeneral/consumer-protection-division/id-theft-prevention/files/DB-Year-to-date-Report-2015.pdf · backfill source
2026-09-25 · added · backfill source

First seen 2026-09-25 (California AG), confirmed by California AG. Record counts are as reported. Not legal advice.

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