Idaho State Tax Calculator (2026)

How Idaho taxes income

Idaho charges flat 5.3%. State tax is a separate calculation from your federal return rather than a share of it — Idaho sets its own schedule and its own definition of taxable income.

• Rate: 5.3% on all taxable income above $4,811
• Brackets: A single rate, so no bracket to cross
• Standard deduction: $16,100 single / $32,200 joint
• Personal exemption: None

Rate figures are as of January 1, 2026 and were checked against Idaho State Tax Commission on 2026-09-28 — 0% band tops of $4,811 single and $9,622 joint against the Idaho State Tax Commission rate schedule. Idaho can still change them mid-year.

What catches people out in Idaho

• Idaho applies a single rate of 5.3%, and only to taxable income above $4,811 — below that the rate is nil, so a modest income can owe nothing at all despite the state having an income tax.
• The Idaho standard deduction is $16,100 for a single filer and $32,200 for a couple filing jointly. It is a separate figure from the federal standard deduction and usually much smaller, so itemising is a decision you make once federally and again for the state.
• Income up to $4,811 for a single filer and $9,622 for joint filers is taxed at 0%, and 5.3% applies above it. Both figures were checked against the Idaho State Tax Commission's own published rate schedule, which states them as $4,811/$4,812 and $9,622/$9,623, so the boundary here matches the state rather than only the compilation. The rate was cut from 5.695% to 5.3% by House Bill 40 in March 2025, retroactive to 1 January 2025. Idaho includes the federal standard deduction in its income starting point (footnote o), and indexes the 0% band annually, so confirm the current figure with the Tax Commission before relying on it.

What this estimate leaves out

Three things are deliberately outside this calculation, because they change more often than annually and a confident wrong number does real damage on a tax page.

• Personal exemptions are not applied.
• Local and city income tax is not included. New York City is the significant one nationally.
• State-specific credits, subtractions and income addbacks are out of scope and can move the result either way.

If you have income in India, Idaho is where treaty relief runs out

States are not parties to the India-US tax treaty, and a state credit for "taxes paid to other jurisdictions" almost always means other US states rather than other countries.

So NRO interest, Indian rental income or a gain on Indian shares can be taxed by Idaho with no credit for the Indian tax deducted at source — even though Form 1116 largely neutralises that same tax federally.

The treatment is not uniform across states, so treat this as the general position rather than as Idaho's confirmed one, and check the credit rules with Idaho State Tax Commission before relying on relief.

Sources

• Tax Foundation — 2026 State Income Tax Rates and Brackets
• Idaho State Tax Commission — the authority for Idaho