internal revenue code; conformity

SB 1222 clarifies which version of the U.S. federal tax code Arizona will use for state income tax calculations. It defines "internal revenue code" for different tax years (from 2017 through 2025) by specifying the exact federal tax law in effect on a particular date, including retroactive provisions from major federal laws like the Inflation Reduction Act. This affects Arizona taxpayers and the Department of Revenue, as it determines which federal tax rules apply when calculating state tax liability. The bill does not change tax rates or create new taxes, but ensures Arizona’s tax code aligns with specific federal tax provisions for each taxable year. It is a procedural adjustment to maintain conformity with federal tax law.