Downsizing in Santa Clarita: Prop 19 and Taxes

Published by Michelle & Jon Dubner | Dubner Real Estate Group | Equity Union

If you're downsizing in Santa Clarita, the first question we hear almost every time isn't about boxes or floor plans. It's "will my property taxes go up if I buy a smaller, newer home?" Michelle and Jon Dubner get this question constantly, and the honest answer is: usually not, if you qualify for California's Proposition 19 and file the paperwork correctly. Downsizing also raises a second money question that gets far less attention, which is how much of your sale proceeds you actually keep after capital gains tax. Both questions have real, specific answers, and both deserve a plain explanation before you list.

• Prop 19 lets homeowners 55 and older transfer their property's taxable base-year value to a new home anywhere in California, up to 3 times in a lifetime, if the replacement is purchased within 2 years of the sale.
• Downsizing to a lower-priced home does not automatically mean a lower tax bill without Prop 19; without the transfer, a new purchase is reassessed at full market value.
• The federal capital gains exclusion shields up to $250,000 (single) or $500,000 (married filing jointly) of profit, but a long-held Santa Clarita home can appreciate past that number.
• Both of these are general education, not personalized tax advice. Talk to a CPA before you list so the numbers are right for your specific situation.

More on that in downsizing without the stress.

This is the fear that stops a lot of longtime Santa Clarita homeowners from even looking at smaller homes: "I've had this low property tax bill for 20 years. If I move, won't the county just reassess me at today's prices?" Under normal California property tax rules, yes, a new purchase gets reassessed at the price you paid for it. But Prop 19, which took effect April 1, 2021, changed that specifically for homeowners 55 and older (it also applies to severely disabled homeowners and wildfire or disaster victims). It lets you carry your old home's taxable base-year value over to the new one, so a smaller home doesn't have to mean a bigger tax bill.

According to the California State Board of Equalization, here's the mechanic in plain terms. You can transfer your current home's taxable base-year value to a replacement home anywhere in the state, and you can do this up to 3 times in your lifetime. The replacement home has to be purchased within 2 years, before or after, of selling the original. The value comparison depends on timing: if you buy the replacement before you sell the original, the comparison is 100% of the original home's value. If you buy in the first year after selling, it's 105%. If you buy in the second year after selling, it's 110%. Any amount your replacement home's value exceeds that threshold gets added on top of your transferred base, rather than the whole home being reassessed from scratch. You then have 3 years from the replacement purchase to file the claim, using Form BOE-19-B.

What this means practically for someone downsizing: if you sell a larger, long-held Santa Clarita home and buy a smaller one for less money, you very likely keep close to your old, lower tax bill instead of resetting to a new, higher one. This is one of the most underused benefits in California real estate, mostly because homeowners assume the opposite is true.

Property taxes are one side of the math. The other is what you owe, if anything, on the profit from the sale itself. Under IRC Section 121, the federal home-sale capital gains exclusion lets you exclude up to $250,000 of gain if you're single, or up to $500,000 if you're married and filing jointly, permanently, not just deferred. To qualify, you need to have owned and lived in the home as your primary residence for at least 2 of the 5 years before the sale, and you can't have used this exclusion on another home sale within the past 2 years. These figures are statutory for 2025 returns filed in 2026 and are not adjusted for inflation.

Here's the part we want to be honest about rather than gloss over. That exclusion was set decades ago and has never moved with home prices. If you bought your Santa Clarita home 20 or 30 years ago and it has appreciated significantly since, your actual gain, meaning your sale price minus what you originally paid and any qualifying improvements, can run well past $250,000 or even $500,000. When that happens, the amount above the exclusion is taxable as a capital gain. This is exactly the situation a lot of downsizing sellers find themselves in, because long ownership is often what makes downsizing worth considering in the first place. It's not a reason to avoid selling. It's a reason to know your numbers ahead of time instead of being surprised at tax season.

One thing worth separating out clearly: everything above applies to a living homeowner selling a home they've owned and lived in themselves. If a home came to you through inheritance, the tax math works differently because of a rule called step-up in basis, which resets the property's cost basis to its value at the time of inheritance rather than what the original owner paid. That's a genuinely different topic with its own rules, and we'll cover it in detail in an upcoming post on selling an inherited or probate property. If that's your situation, hold off on applying anything above until we walk through that piece, or talk to your CPA directly.

Yes, every time, and we tell every downsizing client the same thing. Prop 19 and the capital gains exclusion are both real, valuable tools, but they hinge on details specific to your situation: your age, how long you've owned and lived in the home, your filing status, your original purchase price, and the timing of your next purchase. Jon and I can walk you through how these generally work and help you think through timing, but the actual numbers need a CPA or tax professional who can look at your full picture. Getting a rough estimate from your CPA before you list means no surprises after closing, whether you're staying in Santa Clarita, moving elsewhere in Los Angeles County, or leaving the area entirely.

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If you're thinking about downsizing and want to talk through what Prop 19 and the capital gains exclusion could mean for your specific home, call or text us at 661-219-5517. We're happy to walk through the general picture with you before you bring in your CPA for the final numbers.

Michelle & Jon Dubner · Dubner Real Estate Group · Equity Union

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