The $505,000 Line: How the New SALT Deduction Rewards Planning in California

Natalie C. Papagni, CPA

Oct 5

4 min read

Updated: 3 hours ago

The federal deduction for state and local taxes just got four times larger, but not for everyone. Where your income lands relative to one number now decides how much of it you keep.

For most of the last decade, Californians stopped thinking about the SALT deduction. From 2018 through 2024, the federal deduction for state and local taxes was capped at $10,000. For a household paying California income tax and property tax, that limit was reached long before the year was half over. Many stopped itemizing altogether, and the question quietly dropped off the list.

It belongs back on the list. Beginning in 2025, the cap rose to $40,000, and for 2026 it is $40,400. It rises 1% a year through 2029 and is scheduled to return to $10,000 in 2030. For a California household, that's a meaningful deduction again. But the larger cap comes with a condition that turns one income figure into a planning line.

Key points

The 2026 SALT cap is $40,400, available in full up to $505,000 of modified adjusted gross income.
Above that, the cap shrinks by 30 cents per dollar of excess income, reaching $10,000 at about $606,000.
Inside that range, the effective federal rate on extra income is roughly 45% for a household in the 35% bracket.
Pre-tax retirement contributions reduce the income the test is based on. Charitable gifts don't.
The larger cap runs only through 2029, so the planning is multi-year by design.

How the phase-down works

The full $40,400 is available only when modified AGI is $505,000 or less. Above that, the cap shrinks by 30 cents for every dollar of excess income, until it reaches the old $10,000 floor. In 2026, that happens at about $606,000. The thresholds are the same for single and joint filers; married couples filing separately get half of each.

2026 modified AGI	SALT cap
$505,000 or less	$40,400
$530,000	$32,900
$560,000	$23,900
$590,000	$14,900
About $606,000 and above	$10,000

The rate no one sees

Inside that range, a dollar of extra income does two things. It's taxed at your bracket, and it removes 30 cents of deduction. For a household in the 35% federal bracket, that second effect adds about 10.5 cents of federal tax per dollar. The effective federal rate on income in the phase-down range is roughly 45%, before California tax and before any Net Investment Income Tax.

This is why the range matters even for households that would never describe themselves as wealthy. A two-income professional couple can cross $505,000 in a year with a good bonus, a stock sale or a large Roth conversion, without any change in how they live.

Two households with the same five-year income can keep very different amounts of this deduction. The difference is which years each one's income landed in.

Who benefits most

Households under $505,000 whose state income and property taxes exceed $10,000. Many California homeowners in this group can itemize again, and should check every year.
Households between $505,000 and about $606,000. They keep part of the larger cap, and each dollar of income they move out of the range is worth more than it looks.
Households above about $606,000. They're back at $10,000 personally, but may still have options through a business they own.

The levers

The phase-down is driven by modified AGI, so the planning works on the items that move AGI.

Pre-tax retirement contributions to a 401(k), 403(b) or 457(b), and HSA contributions, reduce AGI directly. In the phase-down range, a pre-tax contribution saves both the tax on the income and part of the lost deduction.
Timing income you control. Where you have a say in when a bonus is paid, when stock is sold, or when a property sale closes, moving it between years can keep one year under the line.
Roth conversions add to AGI. A conversion that makes sense in isolation can cost more if it pushes you into the range. Spreading conversions across years, or making them in a lower-income year, avoids that.
Charitable gifts don't help here. They're itemized deductions, taken after AGI, so they don't reduce the figure the phase-down is based on.
Timing state tax payments. State and local taxes count in the year paid. When one year will be under the line and the next over it, when you pay a fourth-quarter California estimate or a property tax installment can shift the deduction to the year where it's worth more.
Rental property taxes are separate. Property taxes on a rental are deducted against rental income and aren't subject to the SALT cap at all.
Business owners have a further option. California's elective pass-through entity tax can move state tax on business income off your personal return, outside the cap entirely.

The engineer and the chess player

Calculating the phase-down is engineering: exact thresholds, exact definitions of modified AGI, an exact 30% rate. Deciding what to do about it is chess. Because the larger cap is scheduled to run only through 2029, the question isn't only how to keep this year under $505,000. It's which years to keep under the line, which years to accept being over it, and where to place the income you control across that window. A plan built on a projection of the next several years answers that. A return filed in April can only report where the line fell.

What to take from this

If your household income is anywhere near $500,000, the SALT deduction is no longer a settled matter. It's a figure that moves with decisions you're making this year. The time to ask where your income is projected to land, and what's still open to you, is while the year is still in progress.

Discuss your situation with Natalie C. Papagni, CPA

If your household income is anywhere near $500,000, a projection of where it will land this year and next, and what is still open to you, is the natural next step. A complimentary 30-minute consultation is the first step.

Natalie C. Papagni, CPA — Tax, Planning & Advisory Services 4275 Executive Square, Suite 200, La Jolla, CA 92037 (858) 754-8277 | service@lajollataxcpa.com | lajollataxcpa.com

Disclaimer: This material is provided for general educational purposes only. It is not tax, legal or accounting advice, and it does not create a CPA–client relationship. Tax outcomes depend on individual facts and circumstances, and figures and rules change from year to year. Consult a qualified professional about your specific situation before acting. Figures reflect 2026 federal rules under Public Law 119-21.