The 5500-EZ must only be filed if the previous calendar year had more than $250,000 in total assets in your Solo 401k plan. The 5500-EZ must then be filed by July 31st of the following calendar year.
For example, if on December 31st, 2018 your Solo 401k plan had more than $250,000 in total assets, then you would need to file your form 5500-EZ by no later than July 31st, 2019.
Where do I send the completed 5500-EZ?
Mail your completed and signed 5500-EZ form to:
Department of the Treasury
Internal Revenue Service
Ogden, UT 84201-0020
For instructions on how to complete the 5500-EZ, please visit the IRS website at http://www.irs.gov/pub/irs-pdf/i5500ez.pdf.
You must file a 5500-EZ if you are terminating your plan
If you're rolling the assets over to another 401k provider you shouldn't need to file a 5500-EZ if you are keeping the same trust and tax ID number. However, it is recommended you check with your new document provider.
If you're closing the 401k completely and distributing the assets, or rolling everything into a self-directed IRA or other qualified retirement vehicle, then you must file and submit form 5500-EZ.