Who Is the Plan Sponsor of a 401(k)? How to Find Yours
The plan sponsor of a 401(k) is almost always the employer that offers the plan — the company named on line 2a of the plan's Form 5500 filing. Type your employer's name below to see its plan and sponsor, or use either of the other two methods further down.
Last updated June 10, 2026
The short answer
Your 401(k)'s plan sponsor is your employer — current or former, whichever company's plan holds the money. A union or multiemployer plan is sponsored by the union or a joint board of trustees instead. A solo 401(k) is sponsored by your own business: you're both the sponsor and the participant.
The sponsor's exact legal name matters more than you'd think. Rollover forms, the IRS, and benefit claims all ask for the plan sponsor as it appears in plan records — which can differ from the brand name on your paychecks ("Acme Holdings LLC" vs. "Acme").
Three ways to find your 401(k) plan sponsor
- Search the plan's Form 5500 (fastest). Use the search box above — company name, EIN, or plan name. The plan page shows the sponsor's legal name, EIN, and address straight from line 2a of the filing. Free, no login.
- Check your plan documents. The Summary Plan Description (SPD), your annual fee disclosure, and most quarterly statements name the plan sponsor and plan administrator.
- Use the DOL's EFAST2 search. The government's own filing search returns the same Form 5500 data in raw form — see how the DOL 5500 search works.
Why the plan sponsor matters
- Rollovers. Transfer paperwork asks for the plan sponsor's name and often its EIN. Getting the legal name wrong stalls the transfer.
- Old and lost accounts. Tracking down a lost 401(k) starts with identifying the sponsor — the filing also names the administrator and recordkeeper to contact.
- Contacting the right party. The recordkeeper (Fidelity, Empower, etc.) handles your account mechanics, but plan-level decisions — loans policy, vesting disputes, QDROs — go through the sponsor/administrator.
Search by your employer's name. Every plan page shows the sponsor's legal name and EIN, the administrator, the recordkeeper, plan assets, and participants.
Look up your 401(k) planIf your employer merged, was acquired, or shut down
Sponsorship follows the company. After a merger or acquisition, the successor company usually becomes the sponsor, and the plan may be renamed or merged into the acquirer's plan. The Form 5500 trail shows this: filings continue under the surviving sponsor, and a terminated plan files a final return. If the search shows no recent filing for your old employer, search the acquiring company's name — and see the lost 401(k) guide for the databases that cover terminated plans.
Live 401(k) plans from the public DOL data. Every plan page shows the sponsor's legal name, EIN, and address from line 2a of the filing.
Search Form 5500 filingsFrequently asked questions
Your employer — the company that offers the plan. For a past job's 401(k), it's that former employer. The sponsor's exact legal name and EIN are on line 2a of the plan's Form 5500, which is public and free to search.
No. Those firms are recordkeepers — vendors the sponsor hires to run the accounts. The plan sponsor is the employer that maintains the plan.
Usually the same company in two legal roles. The sponsor maintains the plan; the administrator operates it. Most Form 5500 filings list the administrator as "SAME" as the sponsor.
Look up the plan's Form 5500: the sponsor's EIN is on line 2b, right under the sponsor's name. A free Form 5500 search by company name shows it on the plan page.
Your own business. The self-employed person (or their entity) establishes the plan, so it is the sponsor — and you're also the participant. Solo 401(k)s file Form 5500-EZ once assets pass $250,000, and those filings aren't in the public dataset.