Can I keep my property tax basis when I sell?

Often, yes. California’s Proposition 19 lets an owner who meets one of three criteria in the statute sell a principal residence and move its assessed value to a replacement home anywhere in the state, even a more expensive one. For a long-held South Bay home assessed far below its market value, that can be worth tens of thousands of dollars a year. The rules are exact, the claim is not handled by escrow, and the order in which you buy and sell changes the math, so it pays to read them before you list.

Who qualifies to transfer a property tax basis under Proposition 19?

The statute names three categories, and you need to meet one of them on the date the original home sells: a person who is 55 or older, a person who is severely and permanently disabled, or a victim of a wildfire or a natural disaster declared by the Governor (Revenue and Taxation Code section 69.6). Both the home you sell and the home you buy must be your principal residence, eligible for the homeowners’ exemption. The State Board of Equalization notes that the person making the claim does not have to be the sole owner of the replacement home, and that there is no minimum time you must have lived in the original home.

What are the rules on timing and location?

The replacement can be anywhere in California, and it must be bought or newly built within two years of the sale of the original, before or after. A person qualifying by age or disability can use the transfer three times; the limit does not apply to disaster victims. These rules took effect on April 1, 2021, and they replaced the older system that worked only within a county or between a handful of counties. The Board of Equalization keeps the full comparison and its questions and answers on its Proposition 19 page, and the Los Angeles County Assessor has the local version.

What happens if my next home costs more than the one I sell?

You still keep most of the benefit. If the replacement is of equal or lesser value, the old assessed value moves over unchanged. If it costs more, the difference between the two market values is added to the old assessed value. The law gives you a small allowance depending on timing: the replacement counts as equal or lesser if it costs no more than 100 percent of the original’s sale value when you buy before you sell, 105 percent when you buy within the first year after the sale, and 110 percent when you buy in the second year.

A South Bay example. You sell a Palos Verdes Estates home for $3,000,000 that is assessed at $600,000. Eight months later you buy in Manhattan Beach for $3,500,000. Because you bought within the first year, the comparison figure is 105 percent of $3,000,000, or $3,150,000. The $350,000 by which the new home exceeds that figure is added to your old $600,000, so the new home is assessed at $950,000 instead of $3,500,000. At the 1 percent general levy alone, that is $9,500 a year against $35,000, before voter-approved debt and direct assessments are added to either figure.

Does it matter whether I buy first or sell first?

It does, in two ways. The allowance is smaller if you buy first: 100 percent instead of 105 or 110. And the Board of Equalization states that if you buy the replacement before selling the original, you pay taxes on the replacement’s full market value for the months in between, with no refund for that period. Neither point is a reason to avoid buying first if that is how you secure the right house. They are costs to weigh against the cost of a bridge loan or a rent-back, and they are easy to estimate in advance. Our page on how long it takes to sell covers the ways to order the two transactions.

How and when do I file the claim?

With the assessor of the county where the new home is, after both transactions are complete and you have moved in. Escrow does not file it for you. The form is BOE-19-B for a claim based on age, BOE-19-D for disability and BOE-19-V for disaster. File within three years of buying the replacement and the relief reaches back to the purchase date, with any excess taxes refunded. File later and the relief begins only with the year you file. After any purchase in Los Angeles County you should also expect one or two supplemental tax bills, which are mailed to you directly and are not paid from a lender’s impound account. Once the claim is granted the assessor corrects them, so file promptly and keep the bills.

What about leaving the house to my children?

Proposition 19 narrowed that rule, and families planning around a long-held home should know the current version. A transfer between parent and child keeps the parent’s assessed value only when the home was the parent’s principal residence and becomes the child’s principal residence, with the child moving in and filing for the homeowners’ exemption within one year. Even then the protection is capped: the assessed value plus $1,044,586, a figure that applies to transfers through February 15, 2027 and adjusts every two years. Market value above that line is added to the assessment. A home the children intend to rent out or keep as a second home is reassessed in full. For many South Bay families this changes whether the next generation keeps the house or sells it, and it is a conversation to have with an estate attorney and a CPA while the choices are still open. The form is BOE-19-P, and the Board of Equalization’s page linked above works through examples.

How do I use this when planning a sale?

Start with three numbers: your current assessed value, which is on your tax bill; what your home would sell for; and what the replacement is likely to cost. With those we can show you the new assessment under each timing option and what it means each year, side by side with staying put. Send us the address and the kind of place you are considering next, and we will prepare the comparison for you to take to your CPA.

Rules and figures are from the California State Board of Equalization, the Revenue and Taxation Code and the Los Angeles County Assessor and Property Tax Portal, checked September 20, 2026. The examples are illustrations using the 1 percent general levy only; actual tax rates vary by tax rate area. Eligibility is decided by the county assessor on the facts of each claim. This page is general real estate information, not tax or legal advice. Consult your CPA or tax attorney before acting.