Can a Taxpayer Apply an Extension Payment in 2021 That Results in an Overpayment to the First Quarter Estimated Tax Payment for 2021?
Let’s start this article by noting that this is an issue that likely costs more in wasted time to research and resolve than the dollars that might be saved by finding the tax payment can be pushed back a month. But many advisers are stressing quite a bit over trying to answer this question: “If a taxpayer pays money with an extension filed on May 17, ends up with an overpayment when the return is finally filed and applies the amount to the 2021 return, will that overpayment be treated as paid as part of the first estimate due on April 15?”
Some advisers have gotten used to “beefing up” the payment with extensions, expecting the taxpayer to be overpaid when the return is completed. That expected overpayment is meant to cover the first estimated tax payment due for the following year. Two reasons are offered for going this route:
It eliminates the need to prepare both an extension and an estimated tax voucher at the original due date, as well as allowing the taxpayer to make a single payment and
It provides some protection to the client from a failure to pay penalty and interest on the return being extended if it turns out there’s more income than expected (albeit at the potential cost of now incurring some underpayment of estimated tax penalty on the following year’s return).