Corporate income tax: rate; incremental rollback of rate to 4.25%; provide for. Amends sec. 623 of 1967 PA 281 (MCL 206.623).

HB 4737 gradually reduces Michigan's corporate income tax rate over time. It sets a schedule where the rate starts at 6.0% for business activity before October 1, 2025, then steps down to 5.5% in 2025-2026, 5.25% in 2026-2027, 5.0% in 2027-2028, 4.75% in 2028-2029, 4.5% in 2029-2030, and finally 4.25% starting October 1, 2030. The bill directly affects corporations conducting business in Michigan, applying these changing rates to their taxable income base. It does not alter the tax base calculations or other provisions of the corporate income tax code.