Eisner Advisory Group eisneramper.com Eisner Advisory Group data breach: what happened and what to do
Eisner Advisory Group, the firm behind EisnerAmper, found that an unauthorized party accessed and took files between September 4 and 9, 2023. Letters began going out in April 2025. Exposed data included Social Security numbers, financial account details and medical information.
View all 13,115 breaches- Breach date
- 4 Sept 2023
- Data exposed
- Names, Dates of birth, Social security numbers, Bank account numbers, Medical information, Health insurance information
- Last updated
Eisner Advisory Group LLC, the accounting and advisory firm that operates as EisnerAmper, told people in April 2025 that an unauthorized party had gotten into some of its files in September 2023.
What happened
According to the notice, someone accessed files on the firm's systems between September 4 and 9, 2023, and acquired them. The firm says access was limited to those files. The file review took until early 2025, and notification letters started on April 8, 2025. The breach also appears on the California and Washington Attorney General notification lists.
What was exposed
The data differed from person to person. Reported categories include names, dates of birth, Social Security numbers, financial account information, medical information and health insurance information. Some summaries also list driver's license numbers and passport numbers, so check your own letter for the exact list.
A Social Security number plus a date of birth is enough for identity theft: new credit accounts, tax refund fraud and fraudulent loan applications. Financial account details make bank-related phishing more convincing, because a caller can quote real information back to you.
The company's response
People whose data was involved were notified by mail. A class action over the incident was settled, and a settlement notice was published. Read the notice itself for the deadlines and terms if you got one.
The number of people affected has not been published in the notices we cite. The Washington figure of 2,121 covers residents of one state only, not the total.
What to do if you were in it
- 1
Freeze your credit at all three bureaus
Freezing your credit at Equifax, Experian and TransUnion stops anyone opening new accounts in your name. It's free and you can lift it when you need credit.
- 2
Watch your bank and card statements
If financial account details were in your letter, review statements every week for a few months and report anything unfamiliar to your bank at once.
- 3
Use the credit monitoring if you were offered it
Enroll with the code in your letter before the deadline. Monitoring flags new accounts but doesn't prevent them, so keep the freeze on as well.
- 4
Expect phishing that mentions the breach
Treat unexpected calls, texts and emails that mention this incident as suspect. Don't click links or give details. Contact the company using a number from its own website.
- 5
Check whether your email or phone is in this and other breaches
A free Serus scan checks breach databases for your email and phone number and tells you what to do about what it finds. Serus can't remove data from a breach, but it alerts you when your details turn up.
Frequently asked
Was I affected by the Eisner Advisory Group data breach?
Only a letter from Eisner Advisory Group confirms it. The firm mailed notices starting April 8, 2025. If you worked with EisnerAmper or one of its clients and got no letter, contact the firm directly.
What data was exposed?
Names, dates of birth, Social Security numbers, financial account information, medical information and health insurance information, depending on the person.
Is there a settlement?
Yes. A class action settlement notice has been published. Check it for eligibility and deadlines.
Should I change my password?
The notice doesn't mention passwords. Freezing your credit and watching your accounts matter more here.
Sources
Something wrong or out of date? Tell us and we'll re-check it.
