SALT Tax Deduction Limit for Married Couples: $40,000 Cap and Phaseout

For the 2026 tax year, the SALT deduction cap for married couples filing jointly is $40,400, covering the combined total of state and local income, property, sales, and personal property taxes reported on Schedule A.¹ Couples who file separately are limited to $20,200 each. That ceiling shrinks once income crosses $505,000, disappears entirely for couples who take the standard deduction, and resets to $10,000 in 2030 unless Congress acts again.

One Pool, Not Several

The $40,400 figure is aggregate. Every qualifying dollar of state income tax, property tax, sales tax, and personal property tax competes for the same space. You cannot claim $40,400 for property taxes and another $40,400 for state income taxes; anything above the combined ceiling gives you no federal benefit.²

Married couples filing jointly and single filers get the same $40,400 ceiling. Couples who file separately split it in half: $20,200 per spouse.¹

The Income Phase-Down

The full $40,400 is only available if your modified adjusted gross income (MAGI) stays at or below $505,000 for joint filers in 2026, or $252,500 for those filing separately. Above that line, the cap drops by 30 cents for every dollar of income over the threshold.¹

For a married couple filing jointly in 2026:

MAGI of $505,000 or below: the full $40,400 is available.
MAGI of $550,000: the cap drops by $13,500 (30% of the $45,000 over the threshold), leaving $26,900.
MAGI at or above roughly $606,333: the cap bottoms out at $10,000 and stays there.

The phase-down never pushes the ceiling below $10,000 for joint filers or $5,000 for separate filers.¹ MAGI here means adjusted gross income plus certain excluded income from foreign earnings, Guam, American Samoa, and Puerto Rico.

The Marriage Penalty in the Numbers

A single filer gets a $40,400 cap with a $505,000 phase-down threshold. A married couple filing jointly gets the same $40,400 cap with the same $505,000 threshold. Two unmarried partners living together could stack their individual caps for a combined $80,800 of potential deductions, while a married couple is held to $40,400.¹

Filing separately does not fix this. Each spouse gets $20,200 with a $252,500 phase-down threshold, so the combined ceiling matches the joint amount, but the income phase-down bites sooner on each individual return. For dual-income couples in high-tax states, this can cost thousands in lost deductions.

Which Taxes Count

Four categories compete for the SALT space:²

State and local income taxes withheld from paychecks (Box 17 of the W-2) plus any estimated payments made directly to the state.
General sales taxes, as an alternative to income taxes. You pick one or the other for the year, not both. The IRS publishes tables and a sales tax calculator for couples who didn’t save receipts.³
Real estate taxes on domestic property. Foreign real estate taxes do not qualify.¹
Personal property taxes on vehicles, boats, and similar items, as long as the tax is based on value and charged yearly.

In states without an income tax, the sales tax option usually wins. Everywhere else, state income tax alone often eats a large share of the cap before property taxes are even counted.

Some common payments look like taxes but do not qualify: homeowners’ association fees, water and sewer charges, trash collection, transfer taxes on property sales, federal income tax, Social Security tax, and estate or inheritance taxes.² Assessments for local improvements like new sidewalks or streets only qualify to the extent they cover maintenance, repair, or interest, not the original construction.

Business Taxes Sit Outside the Cap

State and local taxes tied to a trade, business, or income-producing activity are not subject to the $40,400 ceiling.¹ If one spouse runs a sole proprietorship, the state income tax attributable to that business comes off on Schedule C as a business expense. The same principle applies to state taxes on rental property income. The cap only restricts personal itemized taxes on Schedule A, so the business slice is separate.

This matters most for couples where one spouse has self-employment income alongside W-2 wages. The business portion is deducted before you start counting toward the cap at all.

You Have to Itemize First

None of this helps unless your itemized deductions beat the standard deduction. For 2026, the standard deduction for married couples filing jointly is $32,200.⁴ With the higher SALT cap, more homeowners in high-tax areas will clear that bar than under the old $10,000 limit. A couple paying $25,000 in property taxes and $15,000 in state income taxes now gets $40,000 counted toward itemizing instead of being stopped at $10,000.

Add mortgage interest and charitable giving on top, and itemizing usually wins. If the total still falls short of $32,200, take the standard deduction; there is no partial credit for itemized amounts that don’t reach the threshold.

Timing Payments Between Years

Because the cap resets each January, when you pay certain state and local taxes can shift deduction value between years. Property taxes are only deductible in the year they are officially assessed under state or local law, so paying early does not always move the deduction earlier. State fourth-quarter estimated income tax payments are more flexible: the January 15, 2027 payment can be made in December 2026 and counted on the 2026 return, but then it cannot be claimed again on 2027.

Accelerating a payment only helps if you have room under the cap in the earlier year. If you are already at $40,400 for 2026, paying more in December is wasted. Couples well under the cap one year and expecting to exceed it the next can bunch payments into the lower year to capture more of the deduction.

Where It Goes on the Return

Qualifying taxes are reported on Schedule A of Form 1040:²

Line 5a: state and local income taxes, or general sales taxes if you elect that option.
Line 5b: real estate taxes on domestic property.
Line 5c: personal property taxes on vehicles and similar assets.

Pull state withholding from Box 17 of each spouse’s W-2 and add any estimated payments made during the year. Property tax figures come from county statements or mortgage escrow records. Vehicle registration renewals often list an ad valorem portion that qualifies separately from flat fees that do not. The total of lines 5a through 5c is then measured against the cap and any phase-down that applies based on MAGI. Tax software calculates this automatically; hand filers need to run the phase-down themselves.

What Changes After 2029

The current cap is temporary. The $40,000 base set by the One Big Beautiful Bill Act steps up by 1% each year through 2029, landing near $41,616 in that final year. Starting in 2030, the ceiling drops back to $10,000 for joint filers and $5,000 for separate filers, and the MAGI phase-down disappears with it.¹

Congress could extend or change the cap before then, but any financial decision that leans on this deduction should be built on the law as written: $40,400 for 2026, small annual bumps through 2029, then a hard reset to $10,000.

1
Office of the Law Revision Counsel. 26 USC 164 – Taxes
2
Internal Revenue Service. Topic No. 503, Deductible Taxes
3
Internal Revenue Service. Use the Sales Tax Deduction Calculator
4
Internal Revenue Service. Revenue Procedure 2025-32