Idaho Income Tax 2026

Idaho has a flat 5.30% income tax for 2026. The standard deduction is $16,100 (single) / $32,200 (married filing jointly). Flat 5.3% individual income tax on all taxable income (tax year 2026), classified as flat by the Tax Foundation. Rate cut from 5.695% to 5.3% by House Bill 40, signed by Gov. Little March 6, 2025 and applied retroactively to Jan 1, 2025; same 5.3% applies in 2026 (confirmed by Idaho State Tax Commission, Tax Foundation 2026, and Governor's office). Idaho conforms to the federal AGI starting point and adopts the federal standard deduction ($16,100 single / $32,200 MFJ for 2026, reflecting OBBBA inflation adjustments); no separate state standard deduction amount and no personal exemptions. Idaho's rate schedule technically exempts the first roughly $4,489 (single/HOH) and $8,978 (MFJ) of taxable income before 5.3% applies, but the structure is effectively a single flat rate. No local or city income taxes in Idaho. Social Security benefits are fully exempt. Idaho offers a retirement-benefits deduction for qualifying recipients (certain government, military, firefighter, and police pensions) subject to age (65+, or 62+ if disabled) and income limits; HB 40 also expanded the exemption for military pensions. Grocery credit available to residents in lieu of taxing food.