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HEAD-TO-HEAD TAX COMPARISON · 2026

COUNTRY A Washington VS COUNTRY B Idaho

Side-by-side analysis of income tax, effective rates, and take-home pay for Washington and Idaho in 2026.

Daniel · CountryTaxCalc Updated May 2026 Tax Comparison 2026
Calculate your take-home → See all comparisons →
OVERVIEW
Washington’s lack of personal income tax is a major advantage for wage earners, saving a $100,000 earner roughly $4,983 per year compared to Idaho’s 5.3% flat tax (reduced from 5.8% in 2026). The gap grows significantly at higher incomes. Washington does levy a 7% capital gains tax on gains above $2…
Section 01

The Big Picture

Top-line rates and effective take-home for a typical earner — including income tax, social contributions, and applicable surcharges.
🌲
COUNTRY A
Washington
TAX RATE
0%
No Income Tax on Wages
No personal income tax; 7% capital gains tax on gains above $262,000
🥔
COUNTRY B
Idaho
TAX RATE
5.3%
Flat Income Tax
5.3% flat income tax rate on all taxable income (reduced from 5.8% in 2026)
TYPICAL ANNUAL DIFFERENCE
Moving from Idaho → Washington at $100,000
$4,983
That's $415/month back in your pocket
Section 02

Tax Savings by Income Level

Net take-home after all income tax, social contributions, and surcharges — for a single employee with no dependents.
GROSS INCOME
🌲 WA TAX
🥔 ID TAX
SAVINGS
10-YEAR
$50,000
$0
$2,308
$2,308
$23,080
$75,000
$0
$3,646
$3,646
$36,460
$100,000
$0
$4,983
$4,983
$49,830
$150,000
$0
$7,658
$7,658
$76,580
$250,000
$0
$13,010
$13,010
$130,100
$500,000
$0
$26,169
$26,169
$261,690
💡

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🌲

Washington Pros & Cons

+ PROS
  • 0% personal income tax on wages and salary
  • No tax on Social Security or pension income
  • Strong technology sector job market (Seattle, Redmond, Bellevue)
  • Lower property tax (~0.98%) than many high-income-tax states
− CONS
  • High sales tax (6.5% state; 10%+ in Seattle metro with local add-ons)
  • B&O gross receipts tax applies to most businesses regardless of profit
  • 7% capital gains tax on gains above $262,000 (since 2023)
  • High cost of living in western Washington / Puget Sound region
🥔

Idaho Pros & Cons

+ PROS
  • No capital gains tax
  • No B&O or gross receipts tax on businesses
  • Lower sales tax (6% flat, no local add-ons beyond 3%)
  • Lower cost of living and property tax (~0.69%) than western Washington
− CONS
  • 5.3% flat income tax on all taxable income
  • Smaller economy and fewer high-paying jobs than Washington
  • Lower average wages mean income tax costs more relative to earnings
  • Less developed public transit infrastructure
FAQ

Frequently Asked Questions

Does Washington State have a capital gains tax?

Yes. Since 2023, Washington levies a 7% capital gains tax on long-term capital gains above $262,000 per year. This is separate from income tax and applies to gains from stocks, bonds, and other assets. Gains from real estate sales and retirement accounts are generally exempt. For most wage earners this does not apply, but investors realising large gains should plan accordingly.

What is Washington’s B&O tax and does it affect me?

The Business & Occupation (B&O) tax is a gross receipts tax on the revenue of businesses operating in Washington. Unlike a corporate income tax, it applies regardless of whether the business is profitable. Rates vary by industry (e.g., 0.471% for retail, 1.5% for services). Idaho has no equivalent tax. For sole proprietors and small business owners, this can be a meaningful consideration when comparing the two states.

Is Spokane, WA cheaper than Boise, ID?

Spokane and Boise are both significantly cheaper than Seattle. As of 2026, Boise has experienced rapid population growth that has driven housing prices up sharply, narrowing the cost gap. Spokane generally offers lower housing costs than Boise now, and you’d also avoid Idaho’s 5.3% income tax. The Spokane metro is a popular destination for people who want Washington’s tax advantages at lower cost than the Puget Sound.

How does Idaho’s flat tax compare to other Mountain West states?

Idaho’s 5.3% flat rate (reduced from 5.8% in 2026) is higher than Colorado’s 4.4%, Utah’s 4.55%, and Nevada’s 0%. It is lower than Montana’s top rate of 5.65%. Among Mountain West states, Idaho now sits below Montana. However, compared to Washington’s 0% on wages, Idaho’s rate still represents a significant annual cost for earners at every income level.
From the brief
PT38.4%−9.6 vs. headline
CY17.8%incl. 60-day rule
AE 0.0%substance required
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