Do I need to file Form 5500-EZ for my Solo 401(k)?
The direct filing test for one-participant plans: asset threshold, final year, deadline, and filing method.
Summary
A one-participant Solo 401(k) generally files Form 5500-EZ when combined one-participant plan assets exceed $250,000 at year end, or when the plan has a final year because all assets were distributed or transferred. Example: a sole-prop plan holding $310,000 on 12/31/2025 must file by July 31, 2026. Missing the deadline can trigger an IRS late-filing penalty of $250 per day, capped at $150,000 per plan year.
IRS filing trigger: over $250,000 in combined one-participant plan assets, or a final plan year.
| Main threshold | $250,000Measured across one-participant plans maintained by the same employer. |
|---|---|
| Final year | Return can be required below the thresholdUse this when all assets were distributed or transferred. |
| Calendar-year due date | July 31The due date is the last day of the 7th month after the plan year ends. |
The two Form 5500-EZ triggers
For a simple owner-only Solo 401(k), the first question is whether combined one-participant plan assets maintained by the employer were more than $250,000 at the end of the plan year. The second question is whether the plan had a final year because all assets were distributed or transferred. Either path can create a Form 5500-EZ task.
Four practical outcomes
The answer usually falls into one of four buckets: likely file because combined one-participant plan assets are over $250,000; likely no annual filing because an ongoing plan is at or below $250,000; final return because the plan fully distributed or transferred assets; or out of scope because employees, late filing, amendments, notices, controlled groups, complex assets, or professional judgment are involved.
The filing method is a separate test
After the filing trigger, the sponsor still has to check whether paper filing is allowed. Sponsors required to file at least 10 IRS returns of any type during the calendar year generally need to file Form 5500-EZ electronically through EFAST2. That threshold is about filing method, not whether the form is required.
What the packet should prove
A clean packet should show the plan name, sponsor, EIN, plan number, plan year, beginning assets, ending assets, contributions, distributions, participant loan facts, filing-method check, and any final-return indication. Those facts should tie back to brokerage, custodian, trust, and plan records the signer keeps outside the app.
What this product does not decide
Solo 5500 Desk does not decide plan eligibility, correction strategy, deduction treatment, investment valuation, or whether a complex plan design is compliant. The product stays in the self-preparation lane for simple, original, on-time one-participant defined contribution cases.
Common questions
What is the asset threshold for Form 5500-EZ?
The IRS uses a $250,000 combined threshold for one-participant plans maintained by the same employer. If the combined total is more than $250,000 at the end of the plan year, each plan in the filing lane may need its own Form 5500-EZ.
Do I need to file below $250,000?
Usually no for an ordinary ongoing one-participant plan, but a final plan year is different. A plan that distributed or transferred all assets can still need a final Form 5500-EZ even below the ordinary threshold.
Who is responsible for the filing?
The plan sponsor or plan administrator remains responsible for the accuracy, review, signature, and filing. Packet software can organize facts, but it does not become the plan administrator.
Does Solo 5500 Desk file the return for me?
No. Solo 5500 Desk prepares a self-review packet and filing checklist. The signer reviews and files through the official paper or EFAST2 path when required.
Related guides
Solo 401(k) $250,000 threshold for Form 5500-EZ
How the IRS $250,000 one-participant plan asset threshold works for Solo 401(k) Form 5500-EZ filing.
Form 5500-EZ vs Form 5500-SF for a Solo 401(k)
How a one-participant plan should think about the two short Form 5500-series lanes before preparing a packet.
Final Solo 401(k) plan year: when Form 5500-EZ still matters
Why a terminating one-participant plan can still have a Form 5500-EZ filing even below the normal asset threshold.
Official sources
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