Idaho Income Tax Calculator 2026 — Flat 5.3% Rate, Take-Home Pay
Idaho keeps it simple: a flat 5.3% income tax for 2026 on taxable income above the standard deduction. This free calculator applies the 2026 federal standard deduction Idaho uses ($16,100 single / $32,200 joint / $24,150 head of household) and shows your bill, effective rate, and monthly take-home.
Idaho Income Tax Calculator (2026)
2026 Idaho flat tax, done right — 5.3% on taxable income, take-home in seconds.
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1 Enter your income
Wages and other income before deductions.
Idaho uses the federal standard deduction for your status.
2 Settings
Apply standard deduction
2026 federal amounts Idaho follows: $16,100 single / $32,200 joint / $24,150 head of household.
Include $10 Permanent Building Fund tax
Idaho adds this flat $10 to most individual returns.
3 Calculate Idaho tax
Working…
✅ Done — your 2026 Idaho tax estimate
How it works
- Step 1 — Enter your annual income and filing status.
- Step 2 — Toggle the standard deduction and the $10 Building Fund tax.
- Step 3 — Get your taxable income, flat 5.3% tax, effective rate, and monthly take-home.
Math: tax = 5.3% × max(0, income − standard deduction). Idaho has taxed income at a flat rate since 2023 (5.3% since 2025).
Everyday uses
- Idaho residents — estimate your state tax before filing Form 40.
- Movers — compare Idaho’s flat 5.3% with graduated states you’re leaving.
- Freelancers — set aside the right amount each quarter.
- Budgeters — turn gross pay into realistic monthly take-home.
Note: estimates only — credits (like the grocery/food tax credit) are not modeled.