Three Data Breach History
WebsiteThree is a UK mobile network operator, part of CK Hutchison.
This page shows all data breaches of Three. View the complete breach timeline, records exposed, root causes, and AI breach risk score. BreachHistory tracks disclosed data breaches worldwide.
Data Breach Timeline — All Three Breaches
- 2017 2017 — Three: Hackers broke into Three's customer database with… 200.0K records Share
- 2016 2016 — Three: Hackers broke into Three's customer database with… 200.0K records Share
- 2012 2012 — Three: Hackers were able to access the user names and… 82.0K records Share
- 2010 2010 — Three: Three Rivers Community College may have suffered a… Unknown records Share
Three Data Breach Summary
This page tracks the Three data breach history and cybersecurity incidents affecting Three. BreachHistory currently indexes 4 publicly disclosed or catalogued incidents spanning 2010 through 2017, with approximately 482 thousand records reported as exposed across all indexed events. These totals may include overlapping datasets or third-party estimates and should not be interpreted as unique affected users.
The Three breach timeline includes major data breaches, cyber attacks, data leaks, credential exposures, API abuse, and other security incidents. Each incident provides details on the estimated records exposed, attack method, affected data types, and supporting public sources. Currently, 0 incidents are company-confirmed.
Largest Three Data Breaches
The largest indexed incidents include the 2017 — Three: Hackers broke into Three's customer database with…, the 2016 — Three: Hackers broke into Three's customer database with…, and the 2012 — Three: Hackers were able to access the user names and…. Record counts originating from threat actors or leak sites should be treated as estimates unless confirmed by Three or a regulator. Below is the list of large data breaches:
- 2017 2017 — Three: Hackers broke into Three's customer database with… — about 200.0K records exposed · Catalogued incident
- 2016 2016 — Three: Hackers broke into Three's customer database with… — about 200.0K records exposed · Catalogued incident
- 2012 2012 — Three: Hackers were able to access the user names and… — about 82.0K records exposed · Catalogued incident
What Information Was Exposed?
Depending on the incident, exposed data may include email addresses, passwords, phone numbers, names, profile information, account identifiers, and other personal information (PII). The exact data varies between incidents, so review each breach page before assuming your information was affected.
Three Data Breach 2026
At the time of this update, no Three data breach has been catalogued for 2026. New incidents are added as official disclosures, regulatory filings, or credible cybersecurity reports become available.
What To Do If You Were Affected
If you believe your account may have been involved in a Three data breach, change any reused passwords, enable multi-factor authentication (MFA), monitor your account for suspicious activity, and be cautious of phishing emails or fake breach notifications.
This Three breach history is maintained by BreachHistory using public disclosures, regulatory filings, security research, and clearly labelled third-party claims. For the complete breach timeline, records exposed, incident details, and AI Breach Risk Score, explore the sections on this page.