In a letter of support to Congressman Darin LaHood (R-IL), the American Institute of CPAs (AICPA) expressed its endorsement of provisions of H.R. 8864, the Tax Administration Simplification Act, which would apply the mailbox rule to electronically submitted tax returns and payments and would revise the estimated tax payments deadline to fall on a true quarterly interval.

In May of 2023, by the Internal Revenue Service National Taxpayer Advocate (IRS NTA), in its Annual Report to Congress, expressed the need to amend section 7502(c) so that electronically submitted tax payments and documents will be treated as submitted on the day they are transmitted, even if the IRS processes them at a later date. This practice – known as the mailbox rule – already applies to payments and documents sent to the IRS through traditional mail.

The legislation also incorporates the recommendation to revise the “quarterly” payments to three-month quarterly intervals instead of three-month, two-month, three-month and four-month intervals.