What does it actually cost to buy into Demarest this year? Ask three sources and you get three different numbers, and the one getting the most attention right now is the wrong one to build a budget around.
Redfin's data for the three months ending May 2026 puts Demarest's median sale price at $2.3 million, up 32.7 percent from the same window a year earlier. That is the number circulating in every conversation about the borough right now. It is also built on 12 closed sales, down from 19 the year before. A median that thin moves whenever a couple of large new-construction estates close in the same month, and that is closer to what happened here than any broad repricing of the town.
Meanwhile Demarest already carries the highest average residential property tax bill in Bergen County, and the federal government just rewrote the rule that was supposed to make bills like that easier to carry. The fix sounds simple: the SALT deduction cap quadrupled from $10,000 to $40,000. For most of the households actually shopping in Demarest right now, it barely moves the needle. The real number to know isn't the median price and isn't the tax bill on its own. It's $500,000, the income line buried inside the new cap that decides whether that relief reaches you at all.
The Median Is Real. The Story Behind It Isn't.
Different data sources are measuring different things in Demarest right now, and the gap between them tells you more than any single figure. Zillow's estimate of the average home value sits at $1,566,155, up 17.2 percent over the past year through late June 2026, a steadier and more moderate read than Redfin's median swing. As of mid-2026, homes.com puts the median sale price at $1,670,000, up 4 percent year over year, which is closer still to Zillow's pace than to Redfin's.
A town where the median sale price jumps 33 percent in one data set while a broader average estimate rises 17 percent and another median rises 4 percent isn't repricing uniformly. It means a handful of high-dollar closings, likely new construction on Demarest's East Hill and around streets like Bellaire, are dragging a thin monthly sample upward. If you're shopping the kind of home that actually trades in Demarest at $900,000 to $1.4 million, the 33 percent headline tells you almost nothing about what you'll pay. If you're shopping the $3 million-plus new-construction tier, it might be the more honest number of the three.
The Tax Bill That Actually Explains the Premium
Demarest's 2024 average residential property tax bill was $24,741, the highest of any municipality in Bergen County. Tenafly followed at $23,837, then Alpine at $22,596, Saddle River at roughly $22,400, and Franklin Lakes near $21,000. These five Northern Valley and northern Bergen towns consistently top the list statewide.
The math behind that isn't mysterious. Premium home values push assessed valuations higher across the board. New Jersey's school funding formula sends limited state aid to districts like these, which means local taxpayers cover more of the bill. And a town with almost no commercial tax base has no warehouse or office park to absorb part of the levy, so the entire cost lands on homeowners. Demarest students attend Northern Valley Regional High School at Demarest, which ranked 18th out of 434 high schools in New Jersey for the 2024-25 school year and holds a U.S. Department of Education Blue Ribbon Award. That's a real trade for the money. It's also exactly the kind of premium that keeps assessed values, and therefore tax bills, high.
The $40,000 Cap Was Supposed to Fix This
The One Big Beautiful Bill Act, signed into law in July 2025, raised the federal cap on state and local tax deductions from $10,000 to $40,000 for single filers, heads of household, and married couples filing jointly, with the cap rising 1 percent annually through 2029. For 2026 the figure is $40,400. Absent further legislation, it reverts to $10,000 in 2030.
The part that gets left out of the headline is the phase-out. Once a taxpayer's modified adjusted gross income crosses $500,000 in 2025 (about $505,000 in 2026), the expanded cap shrinks by 30 cents for every dollar of income above that line, all the way down to a $10,000 floor that gets reached at roughly $600,000 of MAGI. A married couple isn't given double the threshold either. The $500,000 line applies whether you file single or jointly.
Here's what that looks like in practice for a joint filer in the 2025 tax year:
| Household MAGI | Effective SALT Cap |
|---|---|
| $500,000 or below | $40,000 |
| $520,000 | $34,000 |
| $550,000 | $25,000 |
| $600,000 or above | $10,000 |
The relief is real below the line. Above it, it disappears fast, and it disappears across a narrow band of income that a lot of high earners cross without noticing until they file.
Why That Line Falls Right Where Demarest Buyers Live
This is where Demarest's numbers connect. Homes.com's own affordability calculator, built around a mid-2026 median price of $1,918,000 with 20 percent down and a 6.58 percent rate, puts the income needed at roughly $419,000 a year to stay within a standard 28 percent debt-to-income guideline.
$419,000 sits close enough to the $500,000 phase-out threshold that plenty of buyers clear it without trying. Bergen County's Demarest-bound buyers are often dual-income professional households, and once you add a bonus year, vested equity compensation, or a spouse's second income, a household budgeting around $419,000 in base income can easily land at $520,000 or $550,000 in modified adjusted gross income once the tax return is actually filed. That's a household losing $6,000 to $15,000 of the deduction they assumed they'd get when they ran the numbers on the way into contract.
The town with the highest tax bill in the county is also, by its own affordability math, positioned to attract exactly the income band where the new federal relief phases out the fastest. The $40,000 cap is real. For a meaningful share of Demarest buyers, the deduction they'll actually claim is closer to half that, or less.
The Other Reason This Year's Number Isn't Moving
Demarest is not one of the roughly 70 Bergen County municipalities that implemented a property revaluation or reassessment for the 2026 tax year. That list includes neighboring Cresskill, along with Paramus elsewhere in the county. Demarest's 2026 assessment appeal deadline fell on the standard April 1 date, the same cohort as Tenafly and Alpine, rather than the later May dates that apply in towns undergoing a fresh town-wide reset.
That distinction matters for how you read an assessed value on any Demarest listing today. In a reassessment year, the number on file is meant to reflect current market value. In a standard year like this one, the assessed value on record may lag behind what the home would actually sell for, and the only way to know is to divide the assessed value by the county's equalization ratio and compare that figure against real comparable sales, not assume the number on the tax card already tells the whole story.
If a buyer or current owner believes an assessment is out of line with market value, New Jersey's Freeze Act can lock a successful reduction in place for additional tax years once a judgment is entered, so a single successful appeal keeps paying off well past the year you file it. On a Demarest home assessed at $1.5 million, a 10 percent reduction produces roughly $2,500 to $3,000 in annual savings, and that savings repeats for as long as the freeze holds.
What This Means Before You Write an Offer
The 33 percent price jump making the rounds is a mix-shift story built on a dozen sales, not a repricing of the whole town. The $24,741 average tax bill is real and it isn't going anywhere on its own. The $40,000 SALT cap that's supposed to soften that bill phases out fast for exactly the income range Demarest's own affordability math points to, which means the after-tax number many buyers pencil in before making an offer is optimistic by thousands of dollars a year. And because Demarest sat outside this year's revaluation cohort, the assessed value on any given listing may not yet reflect what the home would sell for today, which cuts both ways depending on whether you're buying or appealing.
None of that shows up in a median-price headline. If you're comparing Demarest against Tenafly, Alpine, or another Northern Valley town and want the after-tax number instead of the listing number, The Taylor Lucyk Group can run the actual math with you before you write an offer, not after you've closed. Request Your Luxury Home Valuation and we'll start there.
