Frost Bank frostbank.com Frost Bank data breach: what happened and what to do
Frost Bank told Texas regulators that at least 191,848 customers were affected after an unauthorized party downloaded bank files from a vendor's server. Reported data includes names, addresses, Social Security numbers and dates of birth. Letters began going out on May 20, 2026.
View all 13,115 breaches- Breach date
- 6 Dec 2025
- Affected
- 191,848
- Data exposed
- Names, Physical addresses, Social security numbers, Dates of birth
- Last updated
What happened
The Frost Bank breach didn't happen on the bank's own systems. Software vendor Sefas uses an SFTP server (a file-transfer server) for software support, and an unauthorized party downloaded files containing Frost Bank data from it. The downloads happened intermittently between December 2025 and April 2026. Sefas says it first learned of the claim on April 16, 2026, and told Frost Bank on April 22.
Frost Bank reported the incident to Texas regulators, saying at least 191,848 people were affected, and began mailing notification letters on May 20, 2026. Sefas says there is no indication the activity reached beyond that server or continued after April 16.
What was exposed
Reporting on the notices says the files included names, addresses, Social Security numbers, other taxpayer identification numbers, account numbers, dates of birth and loan numbers.
That combination is what identity thieves look for. A name, date of birth and Social Security number are enough to apply for credit in your name, and account and loan numbers help someone pose as your bank when they call or text you.
The company's response
Sefas is offering one year of identity protection and credit monitoring through CyberScout to everyone affected.
What this means for you
If you bank with Frost, expect a letter and read it for what applies to you. Be wary of any message about your account that arrives out of the blue. Real bank fraud teams don't ask for your full card number or a one-time code.
What to do if you were in it
- 1
Freeze your credit at all three bureaus
A freeze stops lenders from opening new accounts in your name. It's free and takes a few minutes each at Equifax, Experian and TransUnion. Lift it temporarily when you apply for credit yourself.
- 2
Sign up for the free monitoring
Use the CyberScout offer in your letter. It runs for one year from enrollment.
- 3
Watch your accounts and set alerts
Turn on transaction alerts in the Frost app, and review statements for charges or transfers you don't recognize.
- 4
Verify bank contact yourself
If someone calls or texts as Frost Bank, hang up and call the number on the back of your card. Never share a one-time code.
- 5
Check whether your email or phone is in this and other breaches
Run a free Serus scan to see which breaches your email address or phone number appear in. Serus monitors breach databases and the dark web and alerts you if your details show up again. It can't remove data that has already leaked.
Frequently asked
Was I affected by the Frost Bank breach?
Frost Bank began mailing letters on May 20, 2026 to the people affected. If you're a customer and got no letter, contact the bank.
What data was exposed?
Reports list names, addresses, Social Security numbers, taxpayer ID numbers, account numbers, dates of birth and loan numbers.
Was Frost Bank itself hacked?
The files were taken from a server run by its software vendor, Sefas, according to Sefas's account.
How many people were affected?
At least 191,848, according to Frost Bank's report to Texas regulators.
Sources
Something wrong or out of date? Tell us and we'll re-check it.
