Leaving San Francisco? Don’t Leave Your Low Property Taxes Behind

You have been thinking about it. Maybe for a while.

The house is too big now. The kids are gone. San Francisco is expensive, foggy, and complicated in ways it did not used to be. San Diego has sun. Palm Springs has warmth. Carmel has quiet. Napa and Sonoma have vineyards and a slower pace that many San Francisco families have been eyeing for years.

And somewhere in the back of your mind, a voice keeps saying: but if I sell, I lose my property taxes.

That voice is wrong. Or at least, it does not have to be right.

There is a California property tax benefit that was significantly expanded in 2021 that most homeowners over 55 either do not know about or do not fully understand. It could change the financial math of leaving San Francisco entirely.

What is the Prop 19 base year value transfer?

Under California's Proposition 19, if you are 55 or older and you sell your primary residence, you can transfer your low property tax base to your new home anywhere in California. Not just in the same county. Anywhere in the state.

This means the Prop 13 assessed value you have been paying taxes on for decades, not the current market value, follows you to your next home.

Here is what that looks like in real numbers.

The scenario: You bought your Sunset District home in 1988 for $300,000. Today it is worth $1.6 million. Your annual property tax bill is roughly $3,600 based on that original assessed value plus inflation adjustments.

Without the transfer: If you sell and buy a $900,000 condo in San Diego without this benefit, your new tax bill would be based on the $900,000 purchase price, roughly $10,800 per year.

With the transfer: You take your $300,000 base with you. Your new tax bill stays close to what you have been paying for decades.

That is a difference of over $7,000 per year. Every year. For as long as you own the home.

Can you buy a more expensive home?

This is the part most people do not know. You do not have to downsize to use this benefit.

Under Prop 19, you can buy up. If your replacement home costs more than the one you sold, you simply pay the tax difference on the amount over your old home's value. You do not lose the benefit entirely; you pay a blended rate.

So if your SF home sells for $1.6 million with a $300,000 tax base, and you buy a $1.8 million home in Carmel or Napa Wine Country, you transfer the base on the first $1.6 million and only pay market rate taxes on the additional $200,000. That is still a significant saving compared to being fully reassessed at $1.8 million.

Thinking about a vineyard property in Sonoma? A waterfront home in San Diego? A larger place than you have now but somewhere less expensive than SF? The math can still work in your favor.

The rules you need to know

• You must be at least 55 years old when you sell your original home. If married, only one spouse needs to meet the age requirement.
• Both properties must be your primary residence. Vacation homes and rental properties do not qualify.
• You must purchase or build your replacement home within two years before or after selling the original.
• The replacement home can be anywhere in California. San Diego, Palm Springs, Napa, Sonoma, Carmel, anywhere.
• You can use this benefit up to three times in your lifetime.
• You must file the BOE-19-B form with the county assessor where your new home is located. You have three years from the date of purchase to file for a full retroactive tax benefit. Missing this deadline can cost you the benefit permanently.

The two year window explained

The order of your transactions matters for how the value threshold is calculated.

Buying before selling: If you buy your replacement home before selling your SF home, the value comparison is 100% of your original home's eventual sale price.

Buying after selling: If you buy after you sell, the state grants a small buffer. The value threshold for an equal or lesser value transfer rises to 105% of your original home's sale price. If your replacement property costs more than that 105% threshold, you simply pay a blended rate on the difference.

This flexibility gives you room to find the right home without being rushed into a bad purchase.

What about leaving California entirely?

This benefit only applies within California. If you move to Arizona, Nevada, Florida, or any other state, you cannot transfer your California property tax base. However, if you are considering a move within California and worried about losing your low tax rate, this benefit removes one of the biggest financial barriers to making that move.

Many San Francisco homeowners who have been reluctant to sell because of the property tax implications do not realize that the math can work in their favor, even when moving to a warmer, quieter part of the state.

One thing to consider before you sell

If you are also thinking about what happens to your home when you pass it on to your children, the calculation changes. The step-up in basis at death can eliminate capital gains tax for your heirs entirely. And the property tax transfer rules for inherited homes under Prop 19 are different from the 55+ transfer rules. These two sets of decisions interact in ways that are worth thinking through carefully before you make any moves.

Read my guide on what happens to property taxes when you inherit a San Francisco home for more on that side of the equation.

The bottom line

If you are 55 or older and own a home in San Francisco, you have a property tax benefit available to you that most people never fully use. It does not disappear when you move. It travels with you, anywhere in California.

Whether you are thinking about San Diego, Carmel, Napa, Sonoma Wine Country, or simply a smaller place somewhere quieter, the financial picture may be more favorable than you think.

If you have questions about how this applies to your specific situation, start with a conversation. No pressure, no obligation, just clarity. Let's Talk.

This article is for informational purposes only and does not constitute legal or tax advice. Please consult a qualified estate attorney and tax advisor for guidance specific to your situation.