Independent public-records tracker. Not a government website.Facts from official state, HHS and SEC filings
BreachRecord

Largest data breaches of 2021

The 3 data breaches first reported in 2021 with the most people affected, using official totals from the filings. Where no official total was filed, the number is the sum of state filings and is labelled "At least". Facts come from official filings with US state attorneys general, the U.S. Department of Health and Human Services (HHS) and the SEC; each breach page links its sources.

Updated Oct 21, 2026 · Showing 1–3 of 3

# Organization First filed People affected Information exposed Filed with
1 20/20 Eye Care Network, Inc.20/20 Eye Care Network, Inc. breach history 4,142,440Official total
  • Social Security number
  • Medical information
  • Health insurance information
  • +3 more
 HHS, Washington AG, California AG
2 NEC Networks, LLC d/b/a CaptureRxNEC Networks, LLC breach history 2,600,000Official total
  • Medical information
  • Date of birth
  • Name
 Washington AG, HHS, California AG
3 T-Mobile USAT-Mobile USA breach history At least 2,079,648Sum of state filings
  • Social Security number
  • Driver's license
  • Date of birth
  • +1 more
 Washington AG, California AG

Other years

People affected is the official total from a filing, or “At least” the sum of state filings where no total was filed. Spotted an error? Report a correction.