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High

investigation open

Updated about 1 month ago

Hallisey & D’Agostino Data Breach

▼ Key takeaways

•Reports suggest a potential breach involving Hallisey & D’Agostino.
•Discovered on April 20, 2026.
•Possible data exposed: Names, Addresses, Social Security Numbers, Payment Information, Phone Numbers, Service Account Details, Payment Histories.
•Affects individuals in: Connecticut, Maine, Massachusetts, Indiana.
•Confirmation level: Confirmed by regulators.

Breach confirmed

The Hallisey & D’Agostino breach is confirmed. If you may be affected, add your details below and we will take it from there.

Detailed summary

Hallisey & D’Agostino, LLP reported a data security incident related to an external system breach. The company disclosed this incident to the Maine Attorney General, and written notices were sent to affected individuals on April 17, 2026.

Affected individuals total 16,683 across multiple states, including at least 10 in Indiana. The breach, which occurred on September 28, 2025, and was discovered on October 21, 2025, may have exposed names, addresses, social security numbers, payment information, phone numbers, service account details, and payment histories. The company is a professional services firm specializing in accounting and tax services for small to mid-sized businesses. The Massachusetts Attorney General also issued a notification related to this incident. It is unclear if there are other data types involved or if the total number of affected individuals will change.

Details about data breaches can emerge over time, and notification processes can be delayed.

Data possibly involved

Names
Addresses
Could be combined with other data for identity theft
Social Security Numbers
Can be used to open fraudulent accounts and file false tax returns
Payment Information
Phone Numbers
May be used for SIM swapping or targeted scam calls
Service Account Details
Payment Histories

Company Response Timeline

Response Grade

Notified consumers within 91–180 days

Breach Occurred

Sep 28, 2025

Company Discovered

Oct 21, 2025

Regulator Notified

Apr 17, 2026

Consumers Notified

Apr 17, 2026

23 days to discover

178 days to notify consumers

Breach Verification Status

Reports Only

Complete

Initial dark web reports of potential breach

Company Confirmed

Complete

Company has acknowledged the breach

Regulator Confirmed

Current

Confirmed by regulatory authorities

Note: Breach verification can take time. Information may evolve as more details become available from companies and regulators.

Case Status:

Investigation Open

We're actively investigating this case and seeking affected individuals.

Were you affected? Submit your information below.

Were You Affected By This Breach?

If you are a customer or have received a data breach notification, you may submit your information as part of our ongoing investigation. Submitting your information is free and does not obligate you.

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Check Your Risk Level

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Do you use Hallisey & D’Agostino?

Yes

What state are you in?

What should I do?

Change your passwords

Update passwords for the affected service and any accounts using the same password

Enable two-factor authentication

Add an extra layer of security to your accounts

Monitor your accounts

Watch for suspicious activity on your financial and online accounts

Watch for phishing attempts

Be cautious of emails or messages claiming to be from the affected company

Consider a credit freeze

Prevent unauthorized access to your credit report

Scan your email for other exposures

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