AZ SB1222

Amends Arizona's definition of "internal revenue code" in Section 42-1001 to reference the IRC as amended and in effect as of January 1, 2025 (instead of January 1, 2024), including retroactive provisions effective during 2024.

Updates Section 43-105 to establish new subsection A defining the IRC for taxable years beginning after December 31, 2024 as the code in effect January 1, 2025, with retroactive provisions from 2024.

Adds new subsection B for taxable years beginning from December 31, 2023 through December 31, 2024, incorporating retroactively effective provisions during that period.

Reorganizes existing subsections C through K (formerly A through J) to maintain historical IRC definitions for taxable years 2022 and earlier.

Makes Arizona's state income tax law conform to federal IRC changes enacted through January 1, 2025.