IRS Form 5500-EZ deadlines
Original due dates and Form 5558 extension dates for the most common Solo 401(k) plan years. Always verify against the official IRS instructions for the form year.
| Filing | Date | Applies to |
|---|---|---|
Form 5500-EZ — Plan year 2024 (calendar year) Original due date for plan year ending December 31, 2024. File on paper if under the 10-return e-filing threshold, otherwise via EFAST2. | Calendar-year one-participant Solo 401(k) plans above $250,000 combined assets at 12/31/2024. | |
Form 5500-EZ — Plan year 2024 with Form 5558 extension Extended deadline if Form 5558 was paper-filed by July 31, 2025. The extension is automatic (no IRS approval letter required). | Calendar-year plans that filed Form 5558 timely for plan year 2024. | |
Form 5500-EZ — Plan year 2025 (calendar year) Original due date for plan year ending December 31, 2025. Last day of the 7th month after the plan year ends. | Calendar-year one-participant Solo 401(k) plans above $250,000 combined assets at 12/31/2025. | |
Form 5500-EZ — Plan year 2025 with Form 5558 extension Extended deadline if Form 5558 is paper-filed by July 31, 2026 with the IRS Ogden, UT service center. | Calendar-year plans that file Form 5558 timely for plan year 2025. | |
Form 5500-EZ — Plan year 2026 (calendar year) Original due date for plan year ending December 31, 2026 (July 31, 2027 falls on a Saturday — deadline rolls to next business day). | Calendar-year one-participant Solo 401(k) plans above $250,000 combined assets at 12/31/2026. | |
Form 5500-EZ — Final return (sample short plan year) Final-year due date for a plan terminating March 15, 2026 — last day of the 7th month after the short plan year ends. | Plans with a final year ending in March 2026 (illustrative example). |