Quick answer

If you itemize deductions on Schedule A (Form 1040), you must choose either state and local income taxes or state and local general sales taxes to deduct on your federal return — not both. Which gives a bigger tax benefit depends on three things: (1) whether your itemized total exceeds the standard deduction, (2) how much you paid in state income tax versus sales tax during the year, and (3) the $10,000 state-and-local-tax (SALT) limit that restricts the total deduction for those taxes (through at least tax year 2025). (See IRS guidance on Schedule A for details: https://www.irs.gov/forms-pubs/about-schedule-a-form-1040.)

Why this choice matters

The choice between deducting state income taxes or state sales taxes is a planning decision, not an automatic IRS swap. The federal deduction can reduce your taxable income and therefore your federal tax. But two important constraints shrink the practical value of this choice:

  • The standard deduction: Many taxpayers now take the standard deduction instead of itemizing. If your Schedule A total (including SALT, mortgage interest, charitable gifts, medical limited items, etc.) doesn’t exceed the standard deduction, the question is moot.
  • The SALT cap: The $10,000 cap on state and local tax deductions (SALT) means high-tax-state residents often hit the ceiling and see less incremental value from larger state taxes. The cap remains in effect through at least tax year 2025. (Tax law: Tax Cuts and Jobs Act; see IRS Schedule A references.)

Both points mean you should run the numbers for your situation before choosing.

How the tax code treats each option

  • State and local income taxes: This is the amount of income tax (and in most cases some state/local real estate or personal property taxes) you paid to state or local governments during the tax year and that you can document. If you live in a state with high income-tax withholding or made large estimated payments, this often produces the larger deduction for itemizers.

  • State and local general sales taxes: The IRS lets taxpayers who live in states with low or no income tax deduct the sales taxes they paid instead. You can use IRS-provided tables to estimate general sales tax based on your income and number of dependents, or you can add up the actual sales tax you paid during the year — and you can include sales tax paid on major purchases (cars, boats, home appliances, etc.) if you use receipts to support them. The IRS describes both approaches in its guidance; taxpayers who choose the sales tax option must substantiate large purchases with receipts if they are claiming actual taxes paid. (See IRS Topic No. 503 and Schedule A instructions: https://www.irs.gov/taxtopics/tc503 and https://www.irs.gov/forms-pubs/about-schedule-a-form-1040.)

Practical steps to decide (walkthrough)

  1. Gather numbers: Pull together state income tax paid (withholding + estimated payments + amounts paid with last year’s return) and sales tax paid (use receipts for big-ticket items; use IRS tables for general sales tax on routine purchases).
  2. Compute both totals on your Schedule A worksheet: (a) income-tax option = state income taxes paid (subject to SALT cap), (b) sales-tax option = IRS table amount + actual sales tax on major purchases (or total receipts total if you tracked everything).
  3. Apply the SALT cap: Your total state-and-local taxes (income or sales + property taxes) can be deducted only up to $10,000. If either option pushes you above $10,000, the excess is not deductible.
  4. Compare itemized total to the standard deduction: If your itemized total (after applying the SALT cap and adding other Schedule A items) is less than the standard deduction, take the standard deduction instead.
  5. Choose the option that increases your total itemized deduction the most and keep documentation for three years in case of audit.

Example calculation

  • Married filing jointly, state income taxes paid during year: $8,000
  • Property taxes paid: $4,000
  • Sales taxes using IRS tables + actual large purchases (if chosen): $9,500

If you choose income-tax deduction: SALT limit applies to income ($8,000) + property ($4,000) = $12,000 → deductible amount = $10,000 (SALT cap).
If you choose sales-tax deduction: sales ($9,500) + property ($4,000) = $13,500 → deductible amount = $10,000 (SALT cap).

In both cases SALT limits the benefit to $10,000, so the difference falls to other Schedule A items (mortgage interest, charitable giving). The key is whether one choice—often sales tax if you live in a no-income-tax state or have large purchases—pushes your itemized total above the standard deduction.

Examples from practice

  • No-income-tax states (Texas, Florida, Washington, Nevada): For clients in these states, sales tax is usually the only SALT-option available. If they made large purchases (vehicle, boat, home appliances) and kept receipts, the sales-tax route often beat the table estimate and produced a larger deduction.
  • High-income-tax states (California, New York): Many clients in high-income-tax states hit the $10,000 SALT cap. In those cases, switching to the sales-tax deduction rarely changes the amount deductible unless they had unusually large, deductible sales tax on one-time purchases and little or no property tax.

Real client vignette (anonymized):
A client in Washington State bought a new electric vehicle and several home appliances in the tax year; with receipts, the actual sales tax on those purchases raised their sales-tax deduction enough to justify itemizing, even though their routine purchases alone (per IRS table) would not have. We documented every receipt, added the IRS table amount for routine purchases, and showed that the itemized total exceeded the standard deduction — producing a net federal tax benefit. In my practice, I always recommend keeping a dedicated folder or spreadsheet for large sales-tax receipts.

Documentation and audit checklist

  • Keep detailed receipts for major purchases (vehicle titles, purchase orders, paid invoices).
  • Save state and local income tax payment records, W-2 withholding statements, and Form 1099s documenting state refunds or payments.
  • If you use the IRS tables, keep a note showing you used the tables and the year’s table amount.
  • Retain records for at least three years from the date you file, as the IRS can question Schedule A items. (See IRS recordkeeping guidance: https://www.irs.gov/recordkeeping.)

Common mistakes to avoid

  • Automatically picking sales tax because you live in a no-income-tax state without checking whether itemizing beats the standard deduction.
  • Forgetting to include property taxes when computing whether the SALT cap applies.
  • Overlooking the benefit of tracking actual sales tax on big-ticket purchases (receipts can beat the IRS table).
  • Not reconciling state refunds in the next tax year: a state refund tied to prior-year state tax deductions can create federal income adjustments.

Tools and resources

Strategies and best practices

  • Run a year-end tax checklist: total your withholding and estimated payments, inventory major purchases, and run both deduction scenarios before filing.
  • If you expect to alternate between standard and itemized (for example, one year you buy a car), consider “bunching” deductible items into one tax year to exceed the standard deduction — see our guide on bunching strategies for itemized deductions: https://finhelp.io/glossary/bunching-strategies-for-itemized-deductions-when-they-work/.
  • Keep a receipts folder or scanned copies of big-ticket purchases; actual sales tax with receipts can beat the IRS table allowance.
  • Work with a tax pro if you live in a high-SALT state to model multi-year effects and state-specific conformity rules.

Bottom line

You only get one SALT-style deduction on Schedule A: state and local income taxes OR state and local general sales taxes. The correct choice depends on your state tax profile, whether you kept receipts for large purchases, and whether itemizing beats the standard deduction after applying the $10,000 SALT limit. Do the math each year and keep documentation for any large purchases you plan to use for a sales-tax claim.

Professional disclaimer: This article is educational and not individualized tax advice. For advice tailored to your facts, consult a qualified tax professional or CPA. Authoritative sources cited include IRS Schedule A guidance and IRS Topic No. 503; readers should check the IRS website for the latest updates.