1. Application of mailbox rule to certain payments made through the Electronic Federal Tax Payment System
“(g) Payments made through the Electronic Federal Tax Payment System
“(1) In general—A qualified Electronic Federal Tax Payment System payment which is required to be made within a prescribed period or on or before a prescribed date under authority of any provision of the internal revenue laws shall be treated as made on the last day of such prescribed period or on such prescribed date, as the case may be.
“(2) Qualified Electronic Federal Tax Payment System payment—For purposes of this subsection, the term “qualified Electronic Federal Tax Payment System payment” means any payment if—
“(A) such payment is made through the Department of the Treasury’s Electronic Federal Tax Payment System (and such payment is not required under any provision of the internal revenue laws to be made in another manner),
“(B) such payment is authorized to be made at the earliest time such payment can be made through such System following such authorization, and
“(C) such authorization is provided within the prescribed period referred to in paragraph (1) or on or before the prescribed date referred to in paragraph (1), as the case may be.
“(3) Application of certain exceptions, including requirement that payment be permitted to be made by mailing—For certain payments to which this subsection does not apply, see subsection (d).”