Guides

Solo 401(k) owner-only eligibility for Form 5500-EZ

The common-law employee question that decides whether a simple one-participant packet is still the right lane.

Summary

Form 5500-EZ is for one-participant plan scenarios, such as owner-only or partner-only plans and their spouses. If the business has common-law employees covered by the plan or facts that could affect coverage, the simple Solo 401(k) packet lane should stop before form preparation.

Hard stop: non-owner common-law employee issues do not belong in this MVP.

SupportedOwner/spouse or partner/spouse planDomestic one-participant defined contribution cases only.
UnsupportedCommon-law employee plan issuesCoverage, controlled group, and affiliated service group questions need review.
OutputSelf-preparation packetNo TPA, ERISA, fiduciary, or plan-design advice.

The owner-only question comes first

Do not start with balances. Start with plan coverage. A Solo 401(k) filing packet is only safe for this product when the plan is in the one-participant lane and the business does not need employee coverage analysis.

Why employees change the risk

Employees can create plan coverage, testing, notice, eligibility, and administration questions. Those questions are not resolved by preparing a Form 5500-EZ packet. They belong with a qualified plan professional or official instructions.

How Solo 5500 Desk handles the boundary

The wizard asks hard-stop questions before collecting form numbers. If the user indicates non-owner employee issues, late filings, amendments, IRS correspondence, or complex plan facts, the product should stop rather than produce a misleading packet.

Common questions

Can I use the app if I hired employees during the year?

Not without a careful scope check. The MVP hard-stops common-law employee and coverage issues because they can move the plan out of the simple one-participant lane.

What about my spouse?

Owner/spouse and partner/spouse one-participant scenarios are part of the intended lane when the other facts are simple and domestic.

Does the app advise on controlled groups?

No. Controlled group, affiliated service group, leased employee, and coverage-combined plan issues are outside scope.

Official sources

IRS Form 5500-EZ filing noticesIRS states the $250,000 asset exception and the last-day-of-the-7th-month deadline. Official source reviewed for this MVP on May 2, 2026.IRS Instructions for Form 5500-EZOfficial instructions explain combined one-participant plan assets, final returns, and electronic filing requirements. Official source reviewed for this MVP on May 2, 2026.IRS one-participant plan project resultsIRS describes common one-participant plan filing mistakes, final-year filings, and failure-to-file penalties. Official source reviewed for this MVP on May 2, 2026.IRS mandatory electronic filing for Forms 8955-SSA and 5500-EZOfficial IRS guidance on the 10-return mandatory e-filing threshold and aggregation rules. Official source reviewed for this MVP on May 2, 2026.DOL EFAST2 filer helpOfficial DOL guidance on electronic filing, IFILE, credentials, and approved software requirements. Official source reviewed for this MVP on May 2, 2026.IRS Form 5558 extensionOfficial extension form context for Form 5500-series returns. Official source reviewed for this MVP on May 2, 2026.