The SALT Cap Quadrupled. NJ Homeowners: It’s Time to Re-Test Your Deductions

For eight years, the math was boring. The $10,000 cap on state and local tax (SALT) deductions meant that for most New Jersey households — even ones paying $18,000 in property tax and five figures in state income tax — itemizing lost to the standard deduction. So millions of returns went on autopilot.

The 2025 tax law changed the inputs. If your return is still on autopilot, you may be leaving real money on the table.

What changed

The SALT cap increased to $40,000 starting with 2025 returns, with small annual increases scheduled after that. Two critical fine-print items:

The phase-down. For households with modified AGI above roughly $500,000, the cap shrinks — reduced by 30% of the income over the threshold — but never below the old $10,000 floor. High earners in the phase-down band face some of the strangest effective marginal rates in the code, which itself creates planning opportunities around income timing.

The expiration. The enlarged cap is scheduled to revert to $10,000 after 2029. This is a window, not a new normal.

Why this matters more in New Jersey than almost anywhere

New Jersey has the highest average property taxes in the country, layered on a state income tax that reaches 10.75%. A typical Morris County household — $15,000 property tax, $20,000 NJ income tax — was throwing away $25,000 of real deductions under the old cap. Under the new cap, that same household deducts all $35,000.

Add mortgage interest and charitable giving, and families who haven’t itemized since 2017 may now clear the standard deduction by a wide margin.

The re-test, step by step

1.          Add your SALT items: property tax on your home, NJ (and NY, if you commute) income tax withheld and paid, including estimated payments.

2.          Cap the total at $40,000 (or your phased-down cap if income exceeds ~$500K).

3.          Add mortgage interest and charitable contributions.

4.          Compare against the standard deduction for your filing status.

5.          If itemizing wins, revisit the strategies that only work for itemizers: bunching charitable gifts, donor-advised funds, and the timing of your January property tax installment and Q4 state estimated payment — paying in December vs. January can move a deduction across tax years.

The phase-down planning angle

If your income sits near the $500K threshold, the cap phase-down effectively adds a surtax on income in that band. Levers that manage MAGI — retirement plan contributions, an S-corp owner’s compensation structure, harvesting losses, timing a Roth conversion in a different year — now carry extra weight, because each dollar of reduced income can also restore SALT deduction.

This is exactly the kind of interaction a software interview never surfaces. It has to be modeled.

The bottom line

The itemize-or-not decision that was settled in 2018 is live again through 2029. Every NJ homeowner should re-run it — once now, and again each fall while the window is open.

Romanchuk CPA LLC has prepared New Jersey and New York returns since 2014. Want your 2026 deductions modeled before year-end, while the timing levers still work? Book a planning session at rfg.tax.

This article is general information, not tax advice for your specific situation. Figures reflect the law as of publication — thresholds adjust annually.