Washington SALT Cap Calculator (Capital Gains Tax)
Enter your MAGI and total state + local taxes below. The estimate applies the OBBBA cap and phase-out line by line — no tax software, no signup.
The short answer: Prakash — at the scenario numbers pre-loaded below, the OBBBA deduction is $2,500, worth about $600 in federal income tax at a 24% marginal rate ($23 per biweekly paycheck). Exact figures update live as you change the inputs.
⚠️ This calculator provides estimates for informational and educational purposes only. It is not tax advice. Results are based on the One Big Beautiful Bill Act (OBBBA) and IRS Schedule 1-A. Consult a qualified tax professional for your specific situation.
Your State's Slice of the $40,000 Cap
Washington's 7% excise on large capital gains is legally an excise tax, but for federal SALT purposes it functions as an income-type tax on gains — the IRS treats it as deductible state tax on income for residents who pay it. Combined with property tax, high-equity Seattle households cross the old $10,000 easily. No wage income tax means most of the SALT total comes from property and the excise together.
The full rules, caps and phase-outs for every deduction are in one table on the OBBBA rules page.
Worked Example
Prakash pays $12,500 total: Washington's 7% capital gains excise plus King County property tax.
- • Deductible amount: $2,500
- • Federal income tax savings: $600 (at the 24% marginal rate)
- • Per biweekly paycheck: $23
Your actual state tax bill sets the input; the cap and phase-out above set the ceiling — the calculator reconciles both.
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Frequently Asked Questions
Does Washington's capital gains excise count as SALT?
For federal deduction purposes it is treated as a state tax on income and counts toward SALT alongside your property tax. Verify the current classification with your tax preparer, as excise-vs-income character has been litigated.
Which taxes count toward the SALT deduction?
State and local income taxes (or sales tax if you elect that instead) plus real property taxes, up to the OBBBA cap after any income phase-out. Federal taxes never count.