Notice 2024-47, page 1.

Notice 2024-47 extends the relief provided in Notice 202433, which waived the estimated tax penalty imposed under § 6655 (for a corporation’s failure to pay estimated income tax) to the extent attributable to the revised corporate alternative minimum tax (CAMT) under § 55, but only with respect to an installment of estimated tax due on April 15, 2024, or May 15, 2024, with respect to a taxable year that began in 2024. In light of the continuing challenges associated with determining the applicability of the CAMT and the amount of a corporation’s CAMT liability under § 55, and in the interest of sound tax administration, the relief from the addition to tax under § 6655 provided by Notice 2024-33 is extended to any installment of estimated tax by a corporate taxpayer with respect to a taxable year that began in 2024 that is due on or before August 15, 2024, to the extent attributable to the CAMT.