Idaho has a top marginal income tax rate of 5.8% for 2026. See the full brackets, standard deduction, and how it stacks up against the national average.
Last updated: May 2026 · Data: state revenue departments, IRS, BLS
Idaho uses a flat income tax system administered by the Idaho State Tax Commission. The top marginal rate for 2026 is 5.8%.
| Taxable Income | Tax Rate (2026) |
|---|---|
| All taxable income | 5.8% |
Idaho income tax starts from your taxable income after deductions. For 2026 (2025 tax year), the federal standard deduction is $15,000 for single filers and $30,000 for married filing jointly, which reduces the income subject to federal tax.
| Standard Deduction (2026) | Amount |
|---|---|
| Federal - Single | $15,000 |
| Federal - Married Filing Jointly | $30,000 |
| Federal - Head of Household | $22,500 |
State standard deductions, personal exemptions, and credits vary and may differ from the federal amounts above. Confirm Idaho figures with the Idaho State Tax Commission.
| Benchmark | Top Marginal Rate |
|---|---|
| Idaho (2026) | 5.8% |
| National average - all 50 states | 4.86% |
| National average - 41 states with an income tax | 5.93% |
| Highest in the U.S. (California) | 13.3% |
| Lowest among states that tax income | 2.5% |
| States with no income tax | 0% (9 states) |
At 5.8%, Idaho's top rate is above the national average of 4.86% (all 50 states).
Idaho moved to a flat income tax rate of 5.8% in 2023, simplifying its previous graduated bracket system. The state has no estate or inheritance tax.
| Idaho Tax Snapshot | 2026 |
|---|---|
| Top Income Tax Rate (2026) | 5.8% |
| Income Tax Structure | Flat rate |
| State Sales Tax | 6% |
| Minimum Wage | $7.25/hour |
| Median Household Income | $69,000 |
| Tax Agency | Idaho State Tax Commission |
Run the numbers for Idaho with our free calculators:
See how nearby states tax income in 2026:
Idaho has a top marginal state income tax rate of 5.8% for 2026. It is administered by the Idaho State Tax Commission.
Idaho uses a flat income tax rate, meaning the same percentage applies to all taxable income.
Idaho applies a single flat rate, so there is effectively one bracket.
The 2026 federal standard deduction is $15,000 for single filers and $30,000 for married filing jointly. Idaho state deductions, exemptions, and credits can differ; verify current figures with the Idaho State Tax Commission.
At 5.8%, Idaho's top rate is above the national average of 4.86% (all 50 states). The national average top marginal rate is 4.86% across all 50 states and 5.93% among the 41 states that levy an income tax.
State income tax in Idaho is collected by the Idaho State Tax Commission. Federal income tax and FICA (Social Security and Medicare) are paid separately to the IRS.