IRS Statute of Limitations

[RWG1950]

A return with a refund that I had e-filed in March of 2021 for the 2020 tax year was only recently (May 15-2023) processed and the requested refund direct deposited.
Haven't a clue why they delayed this so long. Covid for sure, but this was a fairly basic return with no exotic income sources. Customers didn't even itemize.
Was just wondering, in a situation such as this, when would the normal 3 year statute of limitation begin ? 4-15-21 or when the IRS processed the return May 15-2023 ?
Thanks for comments.

[New York Enrolled Agent]

A return with a refund that I had e-filed in March of 2021 for the 2020 tax year
Thanks for comments.

There are different statutes. I'll assume you're interested in the assessment statute. I further assume the return has an acknowledgement of receipt from the IRS.

Section 6501(b) states a return filed before the due date is deemed filed on the due date (in your case 4/15/2021). Section 6501(a) states any additional assessment must be done within 3 years from the date the return was filed. Thus the statute started on 4/15/2021 and runs for three years from that date.

[Rapid Robert]

"when the IRS processed the return May 15-2023"

This got me thinking on tangent. What exactly is the definition, legal or otherwise, of "IRS processing a return"? They can assess a tax or issue a refund on a specific calendar date, but it's pretty clear that they start "processing" the return at the time it is accepted into their computer system(*), and the "processing" can continue for days, weeks, months, even years. I'm curious where you got a specific date of 5/15/2023 as the official date that the IRS "processed" the return.

(*) before accepting the return, the system checks it for all the various business rules and rejects it if not in compliance, which clearly is a step in "processing" the return.