SALT stands for State And Local Taxes. It is a federal itemized deduction that allows taxpayers to deduct certain taxes paid to state and local governments when calculating federal taxable income.
SALT does not give you a dollar-for-dollar refund. Instead, it reduces the amount of income subject to federal income tax.
Generally, SALT includes:
- State and local income taxes
- State and local sales taxes instead of income taxes
- Real property taxes (such as local property tax on a home)
- Personal property taxes that are based on value, such as certain vehicle taxes in some jurisdictions
Important rule: for the income/sales-tax piece, you usually deduct either:
- state and local income taxes, or
- state and local sales taxes
You do not deduct both.
Common non-deductible items include:
- Federal income taxes
- Social Security and Medicare taxes
- HOA dues
- Water, sewer, and trash service charges
- Transfer taxes and stamp taxes
- Special assessments for local improvements in many cases
SALT is claimed on Schedule A of Form 1040, which means it helps only if you itemize deductions.
That creates a two-step test:
- Figure out the SALT amount you are allowed to claim.
- Compare your total itemized deductions to your standard deduction.
If itemizing produces a larger deduction than the standard deduction, itemizing lowers federal taxable income. If not, the standard deduction wins.
Historically, the SALT deduction served a few purposes:
A taxpayer may pay tax to a city, a state, and the federal government on the same income or property. SALT partially acknowledges that overlap.
The United States uses layered taxation. State and local governments fund schools, transit, policing, sanitation, courts, health systems, and other public services. SALT reflects the idea that federal tax law should account for taxes already imposed by other sovereign governments.
Without some deductibility, taxpayers in high-tax states can bear a substantially higher combined tax burden than similarly situated taxpayers in low-tax states.
For many years, the SALT deduction was a normal part of federal itemized deductions. It was often quite valuable in high-tax, high-cost states and cities.
The major modern change came with the Tax Cuts and Jobs Act of 2017, which imposed a federal cap beginning in 2018:
- $10,000 total SALT deduction
- $5,000 if married filing separately
This sharply reduced the value of SALT for many taxpayers in states such as New York, California, New Jersey, and Connecticut.
Supporters argued that:
- SALT disproportionately benefited higher-income taxpayers
- it indirectly subsidized high-tax states
- capping it helped finance broader tax changes
Critics argued that:
- it penalized residents of high-tax jurisdictions
- it hit upper-middle-class professionals, not just the ultra-wealthy
- it changed the balance between federal and state tax systems
For tax year 2025, the IRS instructions reflect a higher SALT limit:
- $40,000 for many taxpayers
- $20,000 if married filing separately
But that larger limit phases down for higher-income taxpayers.
For 2025, the general structure is:
- Start with a $40,000 SALT cap
- If modified adjusted gross income exceeds $500,000 (or $250,000 if married filing separately), reduce the cap by 30% of the excess
- The allowable SALT deduction is not reduced below $10,000 (or $5,000 if married filing separately)
A compact way to think about it:
Allowed SALT cap = max(floor, base cap - 30% × income over threshold)
So the 2025 change helps many upper-middle-income households, but very high earners can still fall back to the old lower floor.
SALT is usually most valuable for people who:
- live in states or cities with meaningful income taxes
- own homes with significant property taxes
- itemize deductions rather than taking the standard deduction
- are not phased down to the floor by the income-based limit
SALT is often less valuable for people who:
- rent
- have few other itemized deductions
- live in low-tax states
- are high enough income to hit the phase-down floor
Most taxpayers in places like New York or California usually deduct income taxes.
Taxpayers in places like Texas, Florida, Washington, or Nevada often consider deducting sales taxes instead, especially if they made large purchases such as:
- a car
- a boat
- home-building materials
- other major taxable purchases
Property taxes can be part of SALT, but they share the same federal cap bucket. That means:
- high state income tax may already use up most or all of the allowed SALT amount
- adding property tax does not necessarily increase the federal deduction if the cap is already reached
This is one reason high-income homeowners in high-tax states often feel the federal cap very strongly.
A key thing many people miss: state returns do not always mirror the federal SALT rules.
Some states decouple from federal itemized deduction rules in important ways. That means a taxpayer can find that:
- the federal return favors the standard deduction
- but the state return still benefits from separate itemized treatment
So the federal answer and the state answer can diverge.
No. A deduction reduces taxable income, not tax dollar-for-dollar.
Usually no. Extensions generally give more time to file, not more time to retroactively generate prior-year deductible tax payments.
Not necessarily. The benefit depends on:
- whether the person itemizes
- the cap in effect
- income-based phase-down rules
- what other deductions they have
Not federally. It generally shares the same SALT limitation bucket.
Suppose a taxpayer has:
- $18,000 of state/local income tax
- $9,000 of property tax
- no major charity or mortgage interest
Their raw SALT total is $27,000.
If the applicable SALT cap is $10,000, they can only deduct $10,000 federally.
If the applicable SALT cap is $40,000, they may be able to deduct the full $27,000, subject to any phase-down.
At a high level, the SALT debate is about whether the federal tax code should:
- accommodate the reality of state/local taxation,
or instead
- limit a deduction that disproportionately helps taxpayers with larger state/local tax bills.
SALT can materially change:
- whether itemizing beats the standard deduction
- how expensive high-tax jurisdictions feel on an after-federal-tax basis
- how homeowners compare to renters
- how much benefit a taxpayer gets from property taxes and state withholding
If you are trying to understand your own SALT position, ask:
- Am I itemizing or taking the standard deduction?
- Should I deduct income tax or sales tax?
- Do I have property taxes that are relevant?
- Am I capped or phased down?
- Does my state return follow different rules from the federal return?
- Did I actually pay the taxes in the relevant tax year?
SALT is one of the most important examples of how federal tax law interacts with state and local taxation. Its basic purpose is easy to understand: it lets taxpayers deduct certain state and local taxes when computing federal taxable income. But its real-world value depends heavily on the current cap, income-based phase-downs, whether the taxpayer itemizes, and whether state rules differ from federal ones.