401(k) Plans Hold More Than Assets. Protect the Data Behind The Plan.

November 14, 2026

Article Summary

401(k) plans hold sensitive personal and financial information that can be used to access participant accounts. This article explains what data needs protection, how it moves through plan administration, and what plan sponsors should expect from employees and service providers who handle it.

The Data Behind the Participant Account Deserves Protection

A 401(k) plan holds more than retirement assets. It also holds the personal and financial data needed to access those assets. For plan sponsors, protecting participant accounts means protecting both.

Throughout a participant’s time in a plan, plan sponsors and service providers collect personal and financial information. That data may include names, Social Security numbers, dates of birth, addresses, compensation, contribution elections, beneficiary designations, account balances, and investment allocations.

All of this information is routine and necessary for managing and operating a plan. Unfortunately, it is also extremely valuable and useful to a person or group with malicious intent seeking to gain unauthorized access, impersonate participants, or steal from the accounts of plan participants.

Protecting participant data requires deliberate planning. Plan sponsors need to know how information is collected, shared, accessed, stored, and protected.

What 401(k) Participant Data Needs Protection?

Plan administration brings together several types of sensitive information:

Names, addresses, email addresses, and telephone numbers
Social Security numbers and dates of birth
Hire dates, termination dates, and other employment information
Compensation and payroll information
Contribution elections and contribution history
Retirement account balances
Beneficiary designations
Loan and distribution information
Bank account or other payment information
Personal identification information
Account credentials and authentication information

A single data point may appear harmless. The risk grows when someone connects a participant’s name with an employer, Social Security number, date of birth, address, or account information. Together, those details can support impersonation, account takeover, or further data theft.

Plan sponsors should know where each type of participant data is stored, who can access it, and where additional copies may exist.

Give Access Only to the People Who Need It

Once plan sponsors identify sensitive participant data, they should determine who needs access to each type of data.

The DOL’s Cybersecurity Program Best Practices recommend access controls based on each person’s role. Access should reflect job responsibilities, not convenience. Sponsors should review access lists regularly and remove permissions promptly when they are no longer needed.

Review or remove access when:

An HR or payroll employee moves to a different position.
A member leaves the plan committee.
Someone with access to a shared drive leaves the company
A third-party consultant’s engagement ends.

Know How Participant Data Moves

Participant data moves among plan sponsors, payroll providers, recordkeepers, custodians, auditors and third-party administrators. That movement is necessary, but every transfer creates another point that needs protection.

The DOL’s Cybersecurity Program Best Practices recommend encrypting sensitive data both while it is stored and while it is in transit. Therefore, plan sponsors must ensure that sensitive information is transmitted through secure portals and avoid more vulnerable methods that provide significantly less control, such as email attachments or simple spreadsheets stored outside of prescribed locations.

Major HR, payroll, and recordkeeping systems deserve attention, but so do downloaded reports, shared drives, and local files. Sponsors should consider the full data lifecycle: collection, authorized use, sharing, recordkeeping, and disposal. Removing unnecessary copies can be as important as adding another security control.

Treat Sensitive Account Changes as Warning Signals

Participant information changes for legitimate reasons. Still, changes to an address, email, phone number, password, multifactor authentication method, banking details, or distribution instructions can affect identity verification or the movement of assets. Sponsors and service providers should confirm the participant’s identity, especially when several changes occur in quick succession.

The DOL’s best practices recommend additional authentication when personal information changes before a distribution. They also call to confirm the identity of the person receiving the funds.

Your Service Providers Hold the Same Stakes

Most retirement plans depend on recordkeepers and third-party administrators that may hold more participant data than the plan sponsor. Outsourcing administration does not remove the sponsor’s responsibility to oversee how that data is protected.

The DOL recommends evaluating a service provider’s cybersecurity practices before selection and monitoring the provider throughout the relationship. Service agreements should address information security, confidentiality, breach notification, privacy and security compliance, records retention and destruction, and cyber insurance.

Before hiring or renewing a service provider, plan sponsors should ask:

What participant information does this provider receive?
Why does the provider need it?
What controls exist over access to the information?
Is sensitive information encrypted?
How does the provider authenticate participant requests?
What happens if the provider discovers a security incident?
Are independent assessments or relevant SOC reports available for review?

Plan sponsors do not need to become cybersecurity experts. They do need to understand how providers handle participant data and how they respond when controls fail. For services providers that have a Service Organization Control audit (SOC audit), the plan sponsor also has a responsibility to review and understand that audit on a regular basis. Larson & Company has a free tool that Plan Sponsors can use to document the review and understanding of the SOC audit report for each service provider. Feel free to contact the Larson Employee Benefit Audit Team if you would like a copy of this checklist.

Protect the Data for as Long as You Hold It

Protecting participant data is not a one-time task. It does not begin and end with setting up a plan, choosing a third-party administrator, or completing a cybersecurity review. Participant information constantly changes as participants take various actions. As the plan and its environment change, the controls in place to protect participant data should evolve as well.

Start with the data already moving through the plan. Identify what information exists, where it goes, who can access it, how it is transmitted and stored, and which safeguards each service provider maintains.

Retirement plans hold both participants’ life savings and the information used to access them. Protecting the account requires protecting the data behind it.

If you need some guidance and direction on how to make sure that your plan participants are protected, reach out to the Larson Employee Benefit Audit Team.

Frequently Asked Questions About 401(k) Participant Data

What 401(k) participant data should a plan sponsor protect?

Protect names, Social Security numbers, dates of birth, contact information, compensation, contribution records, account balances, beneficiary information, banking details, and account credentials. The combination of these details can be especially valuable to someone attempting account takeover or identity theft.

Can plan sponsors email participant census files?

Ordinary email may not provide appropriate protection for files containing sensitive participant data. Use the secure portal, encrypted transfer method, or other approved process established by the plan and its service providers.

Does hiring a recordkeeper transfer responsibility for participant data?

No. Plan sponsors should evaluate the recordkeeper’s cybersecurity practices before selection, address security expectations in the contract, and monitor the provider throughout the relationship.

When should participant account changes receive extra review?

Use additional verification when sensitive personal or banking information changes, especially shortly before a distribution. Several changes made in quick succession can justify added scrutiny.