I received from my solo 41k provider the 1099 for the CRD I made in 2020 from my Solo 401K account. I am now in a position to repay this distribution before filing my 2020 tax return on May 17, 2021. If I do this, I should not have to pay any taxes on the original distribution on my 2020 return, right?. From what I have read, the repayment is treated as a trustee to trustee transfer. In order to accomplish this transfer, do I need to provide the solo 401k provider with any documentation? Does the solo 401k provider need to provide me with any documentation? Can I simply deposit the repayment back into my Solo 401K account?
Correct that no taxes would be due. You don't need to provide the solo 401k plan provider with any documents in order to treat it as a non-taxable direct rollover.
As long as you return the 2020 Cares Act related distribution to an IRA or to the solo 401k by your personal tax return (Form 1040) due date in 2021 plus timely filed extension, you won’t owe income tax for 2020 on the amount distributed. The IRS has posted a Q and A on this topic and is question 7. Click here to view the IRS page. That same IRS page also references more examples surrounding the return of the COVID-19 related distribution found in Notice 2005-92 Sections 4.D, 4.E and 4.F.