A data breach at Kelly Benefits has impacted 550,000 people, with the number of affected individuals growing as the investigation continues.
Benefits and payroll solutions firm Kelly Benefits has confirmed that a recent data breach has affected 550,000 individuals. As the investigation continued, the scale of the impact expanded, revealing that more people were affected than initially believed.
The U.S.-based company provides benefits, payroll, and workforce management solutions to businesses.
In April, Kelly Benefits disclosed a data breach where hackers accessed its systems from Dec 12–17, 2024, stealing sensitive personal data. Initially, the company believed that the incident impacted nearly 264,000 people, including clients of firms like CareFirst, Guardian, and Beam Benefits. Exposed info includes names, SSNs, medical and financial data. The company is notifying impacted individuals on behalf of several customers.
In May, Kelly Benefits started notifying affected individuals on behalf of multiple customers, including CareFirst, Guardian, Beam Benefits, and others impacted by the breach.
In May, the number of impacted individuals grew to 413032, and the investigation was continued.
“On May 2, 2025, Kelly Benefits mailed notice to an additional one hundred thirty-five (135) Maine
residents on behalf of itself and the entities listed in Exhibit A. The information that could have
been subject to unauthorized access for the additional Maine residents includes name, Social
Security number and financial account information.” reads the update provided by the company that was shared with Maine AG. “As such, a total of seven thousand one hundred sixty-four (7,164) Maine residents have now been notified of this event.”
At the end of May, the company revealed that the number of impacted individuals reached 488,000.
Kelly Benefits’ latest update revealed that the data breach affected over 553,660 individuals.
The company did not share details about the attack, no ransomware group claimed responsibility for the intrusion.
The company is offering impacted individuals free credit monitoring and identity protection services through IDX. Kelly Benefits also advises individuals to remain vigilant by regularly monitoring their account statements and credit reports for any suspicious activity. Additional protective steps are outlined in the provided materials.
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Pierluigi Paganini
(SecurityAffairs – hacking, data breach)
