For eight years, the state and local tax deduction lived under a $10,000 ceiling that quietly pushed millions of households out of itemizing altogether. If you live in California, New York, New Jersey, Illinois, or any other high-tax state, you probably watched your property tax bill alone blow past that cap and then gave up — because the standard deduction was simply the better deal.
That math just changed. The One Big Beautiful Bill Act (OBBBA) raised the SALT cap to $40,000, a fourfold jump that suddenly makes itemizing worth a second look for a large slice of homeowners and small business owners. But the new rules come with a catch buried in the fine print: a phase-down that can claw the entire increase back from higher earners, dollar by dollar. Tax professionals have already nicknamed it the "SALT torpedo."
Here is how the new cap works, who actually benefits, and how to figure out whether you should re-itemize in 2026.
A Quick History: How $10,000 Reshaped Itemizing
The SALT deduction lets taxpayers who itemize subtract certain state and local taxes from their federal taxable income. It covers two main buckets:
- Property taxes on your home (and other real estate you own personally)
- Either state and local income taxes or state and local sales taxes — you pick whichever is larger, but you cannot deduct both
Before 2018, this deduction was effectively unlimited. The 2017 tax law capped it at $10,000 per return ($5,000 for married couples filing separately). That single number reshaped how Americans file. Combined with a near-doubling of the standard deduction, the cap pushed the share of households that itemize from roughly 30% down to under 10%. For most filers, the standard deduction won by a mile.
The pain was concentrated geographically. A homeowner in a high-cost suburb might pay $18,000 in property tax and another $20,000 in state income tax — $38,000 of genuine tax expense that the federal code would only recognize $10,000 of. The other $28,000 simply disappeared.
What the $40,000 Cap Actually Does
OBBBA raised the cap to $40,000 for 2025, and the figure is indexed for inflation: $40,400 for 2026. For tax years 2027 through 2029, the cap grows by another 1% each year. Then, unless Congress acts again, the cap reverts to $10,000 in 2030 ($5,000 for married filing separately).
So this is a window — a roughly five-year window — not a permanent change. That matters for planning, because decisions you make now (when to prepay, when to bunch deductions, whether to restructure a business) should account for the cliff at the end of the decade.
For a household that itemizes, the practical effect is straightforward. If you previously deducted $10,000 of a $38,000 SALT bill, you can now deduct $38,000 of it. At a 32% marginal federal rate, that extra $28,000 of deduction is worth about $8,960 in reduced federal tax.
The bigger shift, though, is behavioral. Many filers who switched to the standard deduction in 2018 never looked back. With the cap at $40,000, the itemize-versus-standard calculation flips for a meaningful number of them — and if you do not run the numbers, you will miss it.
The Phase-Down: Meet the "SALT Torpedo"
Here is the catch. The enlarged cap is not available to everyone. It phases down for high earners based on modified adjusted gross income (MAGI).
The mechanics for 2026:
- The phase-down begins once MAGI exceeds $505,000 ($252,500 for married filing separately). The 2025 threshold was $500,000; like the cap, it is indexed up 1% per year.
- For every dollar of MAGI above the threshold, the cap is reduced by 30 cents.
- The cap never falls below $10,000 — the old limit acts as a floor.
Work the arithmetic and the full phase-out point appears. The cap can shrink by at most $30,400 (from $40,400 down to the $10,000 floor). At a 30% reduction rate, that takes $101,333 of excess MAGI. So in 2026, a taxpayer with MAGI of about $606,333 or more is back to the old $10,000 cap — as if OBBBA never touched SALT for them.
A worked example shows why practitioners call it a torpedo. Suppose a married couple has 2026 MAGI of $560,000:
- Excess over the threshold: $560,000 − $505,000 = $55,000
- Cap reduction: 30% × $55,000 = $16,500
- Their SALT cap: $40,400 − $16,500 = $23,900
Now suppose that couple earns one more dollar of income. That dollar does two things: it gets taxed at their ordinary rate (say 35%), and it shaves another 30 cents off their SALT cap — which, if they have enough state and local tax to use the full cap, costs them 30 cents of deduction, or about 10.5 cents of additional tax. Their effective marginal rate inside the phase-down range jumps to roughly 45%.
That is the torpedo: a stealth surtax on income earned between roughly $505,000 and $606,000 of MAGI. It does not show up as a higher tax bracket. It hides inside a shrinking deduction. Taxpayers near that range should think carefully before accelerating income — a year-end bonus, a Roth conversion, or harvesting capital gains can cost more than the headline bracket suggests.
Should You Re-Itemize? Running the Numbers
The decision is simple in concept: add up your itemized deductions and compare the total to your standard deduction. Itemize if the total is larger.
Your Schedule A itemized deductions generally include:
- SALT (capped as described above)
- Home mortgage interest
- Charitable contributions
- Medical expenses above 7.5% of adjusted gross income
The standard deduction is the benchmark you must clear. OBBBA also raised the standard deduction; for 2026 it lands around $16,100 for single filers and roughly $32,200 for married couples filing jointly (the figures are inflation-indexed each year, so confirm the exact number when you file).
Consider a married couple in a high-tax state:
- Property tax: $14,000
- State income tax: $19,000
- Mortgage interest: $11,000
- Charitable gifts: $4,000
Under the old $10,000 cap, their itemized total was $10,000 + $11,000 + $4,000 = $25,000 — below the standard deduction, so they took the standard deduction and ignored Schedule A.
Under the $40,400 cap, their SALT of $33,000 is fully deductible. Itemized total: $33,000 + $11,000 + $4,000 = $48,000. That is roughly $16,000 more than the standard deduction — worth around $3,800 in federal tax at a 24% marginal rate, more in higher brackets.
This couple should itemize. The point is not that everyone should — it is that the answer changed, and last year's conclusion is no longer reliable. If you stopped itemizing after 2018, 2026 is the year to re-run the comparison.
Accurate records make this decision trivial instead of stressful. If your property tax payments, mortgage interest, state tax withholding, and charitable gifts are all tracked in one place throughout the year, the itemize-versus-standard comparison is a five-minute exercise in January. If they are scattered across bank statements, escrow documents, and a shoebox, it becomes a reason to procrastinate — and procrastination is how deductions get left on the table.
The Small Business Angle: PTET Still Matters
If you own a pass-through business — an S corporation, a partnership, or a multi-member LLC — there is a second SALT story you cannot ignore: the pass-through entity tax (PTET) election.
Most states created PTET regimes after 2018 as a workaround to the SALT cap. The idea: instead of the owners paying state income tax personally (where it is subject to the cap), the business entity pays the state tax and deducts it as an ordinary business expense. That deduction reduces the income passing through to the owners — and crucially, an entity-level state tax deduction is not subject to the individual SALT cap. The IRS blessed this approach in Notice 2020-75.
A reasonable question after OBBBA: with the cap now at $40,000, do PTET elections still matter? For many business owners, yes — and here is why.
PTET elections still make sense for owners who:
- Have high income and are caught in the phase-down. A business owner whose MAGI exceeds roughly $606,000 is back to a $10,000 personal SALT cap. For that owner, routing state tax through the entity is the only way to deduct it fully.
- Have state tax liability well above the cap. Even a fully available $40,400 cap leaves a high earner's excess property and income tax non-deductible at the individual level. PTET captures that excess.
- Want to preserve the cap for property tax. If the entity absorbs your state income tax through PTET, your personal $40,400 cap is freed up to cover property taxes and any remaining local taxes.
Notably, earlier drafts of OBBBA contemplated restricting PTET for certain service businesses. Those restrictions did not make the final law — the PTET workaround survived intact. The interaction between the personal cap and an entity-level election is genuinely worth modeling with a tax advisor, because the right answer depends on your income, your state, and how much of your tax bill is property versus income tax.
Timing Strategies: Bunching and Prepayment
For households that land near the itemize-versus-standard borderline, bunching is the classic move. Instead of spreading deductible expenses evenly, you concentrate them into alternating years:
- Itemize in the "heavy" year, when you have stacked two years of charitable gifts, prepaid property tax, and scheduled elective medical procedures.
- Take the standard deduction in the "light" year.
Over two years, bunching can let you capture meaningfully more total deduction than splitting the expenses evenly would.
One important guardrail on prepaying property tax: the IRS only allows a deduction for taxes that have been assessed, not merely anticipated. If your county has issued the bill, paying it early counts in the year you pay. If the county has not billed you yet, writing a check does not create a current-year deduction — it is a prepayment of an unassessed liability. Check the assessment date before you act.
Also keep the 2030 cliff in mind. If the cap reverts to $10,000 as scheduled, the years 2026 through 2029 are the high-value window for SALT-heavy deductions. Where you have discretion over timing — say, a large one-time property tax payment or the year you realize a big state-taxable event — pulling it into the window can be worth real money.
Common Mistakes to Avoid
- Assuming last year's answer still holds. The single biggest error is not re-checking the itemize decision. The cap quadrupled; your conclusion may have flipped.
- Forgetting the income-versus-sales tax choice. You deduct state income tax or state sales tax, not both. Most people in income-tax states pick income tax, but if you made a large taxable purchase — a vehicle, a major renovation — sales tax could win.
- Ignoring the MAGI phase-down when accelerating income. A year-end bonus or Roth conversion that pushes you into the $505,000–$606,000 range carries a hidden cost beyond the headline bracket.
- Overlooking the marriage math. Married filing separately gets half the cap and half the threshold — and the phase-down still applies. Run both filing statuses.
- Prepaying unassessed taxes. Paying a property tax bill the county has not issued yet does not accelerate the deduction.
- Treating the cap as permanent. It is scheduled to revert in 2030. Long-range planning should not assume $40,000 forever.
Keep Your Finances Organized from Day One
Whether the new SALT cap saves you a few hundred dollars or several thousand, capturing that benefit depends on one unglamorous thing: knowing exactly what you paid in property tax, state income tax, mortgage interest, and charitable gifts over the year. Clean records turn the itemize-versus-standard decision into a quick comparison instead of a January scramble.
Beancount.io provides plain-text accounting that gives you complete transparency and control over your financial data — every deductible payment categorized, searchable, and version-controlled, with no black boxes and no vendor lock-in. Get started for free and see why developers and finance professionals are switching to plain-text accounting.
This article is for general informational purposes and is not tax advice. SALT rules, thresholds, and the phase-down interact in ways that depend on your specific income, state, and business structure — consult a qualified tax professional before acting.