Idaho tax return changes for 2026

The Tax Commission’s March 13, 2026 release lists the larger standard deduction, the enhanced senior deduction, and the deductions for qualified tips, car loan interest and overtime. Form 40 filers claim them on line 18; Form 43 filers use line 40 and Idaho Worksheet 1-A.

The bill’s statement of purpose (H0559) says Idaho conforms to the federal law with two exceptions: bonus depreciation, which Idaho has historically not followed, and research costs from 2022 through 2024, which continue on their existing amortization schedule. Research costs from 2025 follow the federal rule, and the same expense cannot support both a deduction and an Idaho credit.

The Commission says early filers who used the old standard deduction will get the larger one automatically. Anyone who wants the senior, tips, car loan or overtime deductions must amend.

Filter your Idaho filers by return date and by Schedule 1-A use; the overlap is your amendment list. HelloBooks practice management can hold that list as tasks with due dates. Idaho sales tax guidance is at /us/sales-tax/idaho.