Idaho Tax Calculator
Idaho applies a single flat rate to all taxable income, having replaced its old tiered bracket system with a flat structure in 2023 and trimmed the rate further since. Idaho conforms closely to federal definitions of taxable income, which keeps the state calculation relatively simple. Enter your income above to see your exact Idaho state tax instantly.
State Tax
$5,300Effective Rate
5.30%Marginal Rate
5.30%| Rate | Bracket Range | Tax |
|---|---|---|
| 5.30% | $0+ | $5,300 |
| Total | $5,300 | |
How Idaho income tax works
- Idaho multiplies your taxable income by one flat rate — there are no brackets to navigate.
- The state's definition of taxable income closely follows the federal return with limited adjustments.
- The calculator shows your total Idaho state tax based on the current flat rate.
Need the exact bracket thresholds instead of an estimate? See the Idaho tax brackets for 2026 .
Estimate your Idaho property tax by county, compare every state at the state tax brackets hub , or see the full tax-by-state directory .
Frequently asked questions
How is Idaho income tax calculated?
Idaho applies one flat rate to your entire taxable income. The calculator multiplies your entered income by that rate to show your exact state tax.
Does Idaho tax Social Security benefits?
No. Idaho excludes Social Security benefits from state taxable income.
When did Idaho move to a flat tax?
Idaho replaced its tiered bracket system with a single flat rate in 2023 and has trimmed that rate further in subsequent years.
How much state tax will I pay in Idaho?
Because Idaho uses a flat rate, your state tax is simply that rate applied to your taxable income. Enter your figures above for an instant total.
Sources
Related insights
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