On October 18, 2024, the U.S. Department of the Treasury (Treasury Department) and the Internal Revenue Service (IRS) issued Notice 2024-74 for the Sustainable Aviation Fuel (SAF) credit created by the Inflation Reduction Act (IRA). According to the IRS’ October 18, 2024, press release, the SAF credit ranges from $1.25 to $1.75 for each gallon of SAF in a qualified mixture. To qualify for the credit, the SAF must have a minimum reduction of 50 percent in lifecycle greenhouse gas (GHG) emissions. The press release notes that the Treasury Department and IRS have issued several notices regarding the SAF credit, including Notice 2024-37, which allows a SAF producer to use the 40BSAF-GREET 2024 model to calculate the GHG emissions reduction percentage for purposes of the SAF credits. In October 2024, the U.S. Department of Energy (DOE) released an updated version of the 40BSAF-GREET 2024 model and accompanying user manual that addresses a calculation issue related to catalyst inputs for the Alcohol to Jet (ATJ) SAF pathways. The press release states that “Notice 2024-74 provides that a taxpayer who uses a 40BSAF-GREET 2024 safe harbor in Notice 2024-37 to calculate its emissions reduction percentage with respect to claims that relate to the sale or use of a SAF qualified mixture after the effective date, must use the October 2024 version of the 40BSAF-GREET 2024 model.”