There are roughly 53 million mortgaged homeowners in the United States. According to Redfin's analysis of Federal Housing Finance Agency data, an astonishing 52% of them — approximately 28 million households — are carrying a mortgage rate below 4%. Of those, roughly 20% have rates below 3%.

To put that in perspective: today's 30-year fixed rate sits at about 6.37%. A homeowner who refinanced at 2.75% in 2021 on a $500,000 loan is saving roughly $1,400 every single month compared to someone who took out the same loan today. That is not a small incentive to stay put.

This phenomenon — economists call it "rate lock" — is one of the primary reasons housing inventory remains so tight nationwide. More than half of all homeowners surveyed by Bankrate in 2025 said there is no mortgage rate at which they would be comfortable selling their home this year. That's up 12 percentage points from the prior year.

The Northeast — Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont, New Jersey, New York, and Pennsylvania — has a homeownership rate of about 63%, with roughly 10 million mortgaged homeowners across the region. Applying the national sub-4% rate share, an estimated 5 to 5.5 million Northeast homeowners are locked into rates below 4%.

But here's what makes the Northeast stand out even more: home equity gains. While parts of the Sun Belt have seen equity decline as pandemic-era price surges corrected, the Northeast has gone in the opposite direction. New Jersey ranked among the top states for year-over-year equity gains in both Q1 and Q3 of 2025.

Princeton is not a typical housing market. With a median home sale price around $1.3 million (Redfin, December 2025) and median home values as high as $1.58 million according to NeighborhoodScout's Q2 2025 data, Princeton sits comfortably among the most expensive real estate markets in the entire country — not just New Jersey.

This means that a Princeton homeowner who locked in a 2.875% rate in 2021 on a $900,000 mortgage isn't just saving a few hundred dollars a month compared to today's rates. They're saving over $2,500 per month. The financial gravity keeping them in place is immense.

The surrounding communities — West Windsor, Plainsboro, Hopewell, Montgomery, and Lawrence — tell a similar story. Demand from Princeton University-affiliated buyers, tech corridor commuters, and New York City transplants has kept prices elevated and inventory thin. Homes in many of these zip codes regularly transact above asking price.

The second half of this story is arguably even more striking than the rate-lock phenomenon. ATTOM's Q4 2025 Home Equity Report defines "equity-rich" as owning a home where your total loan balance is 50% or less of the home's market value — meaning you have at least 50% equity. As of Q4 2025, 44.6% of all mortgaged U.S. homes qualify as equity-rich. That's nearly twice the 26.5% share recorded just before the pandemic in early 2020.

Add in the 39.4% of homeowners who own their homes free and clear — no mortgage at all — and over two-thirds of American homeowners have 50% or more equity in their homes. In raw numbers, that's roughly 53–55 million households sitting on generational wealth.

For Princeton-area homeowners specifically, the equity picture is particularly bright. Home prices in Mercer County and surrounding areas have appreciated significantly since 2019, and the Northeast's strong price support has shielded local homeowners from the equity erosion seen in Florida, California, and parts of the Southwest. A homeowner who bought in Princeton for $900,000 in 2018 could be looking at a home worth $1.3M–$1.6M today — meaning they may have crossed the 50% equity threshold even if they only made a modest down payment at the time.

Rate lock is often discussed as a market problem — and for buyers trying to find inventory, it is. But for the homeowners holding those sub-4% mortgages and sitting on 50–70% equity, it represents an extraordinary financial position. Here's how to think about it:

If you're staying: Your locked-in rate and rising equity mean your home is doing heavy lifting for your long-term net worth. The average mortgage-holding homeowner nationally has roughly $299,000–$311,000 in equity as of early 2026. In Princeton, that number is likely considerably higher.

If you're considering moving: The math is harder than it used to be. Trading a 2.75% mortgage for a 6.37% one on a more expensive home is a significant financial event. Many buyers in this position are exploring bridge strategies, exploring all-cash moves enabled by equity, or downsizing to keep payments manageable.

If you're a buyer: The low inventory driven by rate lock means you're competing for a limited pool of homes. In Princeton, homes still sell in about 57 days and frequently above asking price. Working with an experienced local agent who understands off-market opportunities and pricing nuance is more important than ever.

The housing market in Princeton and across Central New Jersey is not frozen — it's evolving. Life events still drive moves: job changes, growing families, retirements, and lifestyle upgrades don't pause for mortgage rates. But the financial calculus for every transaction has fundamentally shifted. Understanding where you stand — on your rate, your equity, and your options — has never been more valuable.

Between the Northeast's outperforming equity gains, Princeton's elite price appreciation, and the significant concentration of homeowners who locked in sub-4% rates during the pandemic window, Central New Jersey homeowners are sitting at an extraordinary intersection of financial strength and market power.

Whether you're evaluating a sale, exploring a refinance strategy, thinking about a HELOC to tap your equity, or simply trying to understand what your home is actually worth in today's market — the data is clear: this is one of the most consequential moments in recent memory to have a clear-eyed view of your real estate position.