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SALT Cap Deduction Calculator

Calculate your deductible state and local tax amount under the $10,000 SALT cap.

Result

Deductible SALT Amount
$10,000.00
Amount Above the Cap (not deductible)
$4,000.00

The SALT deduction (combining state/local income or sales tax with property tax) has been capped at $10,000 total since 2018, regardless of how much you actually paid - this cap disproportionately affects taxpayers in states with higher income and property tax rates.

About the SALT Cap Calculator

The SALT Cap Deduction Calculator shows how much of your combined state income tax and property tax payments you can actually deduct on a federal itemized return, given the $10,000 cap that has applied to the State and Local Tax deduction since 2018. It's useful for homeowners in higher-tax states who want to see the gap between what they paid and what's actually deductible before they itemize.

How It Works

Enter your state income tax paid and your property tax paid for the year. The calculator adds the two together into a combined SALT total, then compares that total against the fixed $10,000 cap, reporting the smaller of the two as your deductible amount and, separately, whatever portion exceeds the cap and provides no deduction.

Total SALT = State Income Tax + Property Tax; Deductible Amount = min(Total SALT, $10,000); Amount Above Cap = max(Total SALT - $10,000, 0)

Formula & Methodology

Because the cap is a flat dollar figure regardless of filing status, income, or state, the calculation is simply an addition followed by a comparison against $10,000. There is no phase-in or partial credit for the excess; every dollar of combined state and local tax above the cap in a given year receives no federal deduction at all.

Examples

A moderate-tax household

A filer pays $8,000 in state income tax and $6,000 in property tax, for $14,000 in combined SALT. Only $10,000 of that is deductible, and the remaining $4,000 provides no federal tax benefit.

A filer under the cap

A filer pays $3,500 in state income tax and $2,200 in property tax, totaling $5,700 in combined SALT, all of which is fully deductible since it falls under the $10,000 limit.

Advantages

  • Quickly shows whether your combined state and local taxes exceed the cap, rather than requiring a manual add-up against a limit that's easy to forget.
  • Separates deductible from lost amounts, clarifying how much of a state tax bill actually offsets federal tax.
  • Useful for a before-and-after comparison when weighing a move to a state with different income or property tax levels.

Common Mistakes

  • Assuming state income tax and property tax each get their own $10,000 allowance, when they actually share a single combined cap.
  • Deducting the full amount paid in state and local taxes without checking it against the cap first.
  • Overlooking that the SALT deduction only helps if total itemized deductions exceed the standard deduction for your filing status.

Edge Cases to Watch For

  • The cap combines state and local income tax (or sales tax, if elected instead) with property tax into one shared $10,000 ceiling, not $10,000 for each category separately.
  • This calculator only models income tax plus property tax; it doesn't include sales tax as an alternative to income tax, an election some filers with little state income tax prefer.
  • The deduction only matters if you itemize. If total itemized deductions, SALT included, fall below the standard deduction, the SALT figure here doesn't change your tax bill.
  • The $10,000 cap applies per return, not per person, so married couples filing jointly face the same ceiling as a single filer.

Common Use Cases

  • Homeowners in states with high property values or income tax rates estimating their real deductible amount.
  • Filers deciding whether itemizing is worthwhile once the SALT cap limits one of their largest deductions.
  • Anyone comparing the tax impact of relocating to a state with a different property or income tax burden.
Written & fact-checked by the Calculateus TeamLast updated August 5, 2026How we verify our formulas

Frequently asked questions

Why has the SALT cap been especially controversial for certain states?

The $10,000 cap doesn't adjust based on where you live, so it affects taxpayers in high-tax states (with elevated state income tax rates and/or property values) far more severely than those in low-tax states, even at similar income levels - this has made the SALT cap a persistent point of political debate between high-tax and low-tax states since its introduction.

Related calculators

Income Tax EstimatorEstimate your US federal income tax using 2025 marginal tax brackets.Self-Employment Tax CalculatorEstimate self-employment tax (Social Security + Medicare) on your net earnings.Sales Tax CalculatorCalculate sales tax and total price for a purchase.VAT CalculatorAdd or remove VAT from a price.

Related articles

Effective vs. Marginal Tax Rate: Why They're So DifferentThese two numbers are often confused, but they answer completely different questions. Here's how to calculate both correctly.What Your Marginal Tax Rate Actually MeansYour marginal tax rate is the rate on your next dollar of income, not your whole income. Here's why that distinction matters so much.How Property Tax Is Calculated on Your HomeProperty tax is based on assessed value, not market value — and the two aren't always the same number. Here's how it actually works.

Conclusion

The SALT Cap Deduction Calculator makes the $10,000 ceiling concrete by turning your actual tax payments into a clear deductible-versus-lost breakdown. It's a starting point for understanding itemized deduction limits, not a full itemized return calculation.

References