For coastal Orange County homeowners 55 and older who want to move without losing a low tax base.
If you are 55 or older, Proposition 19 lets you carry the low property-tax base you have built up on your current home to your next California home, up to three times, so that moving does not reset your taxes to what a brand-new buyer would pay. This calculator estimates what your new base and your annual savings would look like.
For a long-time homeowner in Newport Beach, Costa Mesa, or Corona del Mar, the property-tax bill is often the quiet reason a move never happens. You have owned the house for decades, your assessed value is far below today's market, and the fear is that selling means starting over at a much higher tax bill on the next place. Proposition 19 is the rule that changes that math. The calculator below shows you roughly where you would land.
Enter three numbers. You can find your current taxable value on your most recent property-tax bill or on the county Assessor's site, listed as your assessed or factored base-year value.
Prop 19 does not simply freeze your old taxes on a bigger home. It works in two parts. If your replacement home costs the same as, or less than, your sale price, your old taxable base transfers over unchanged. If the replacement costs more, you keep your old base and add only the difference above an adjusted threshold. The adjusted threshold is your sale price multiplied by a timing factor: 100% if you buy before or at the sale, 105% within the first year after, and 110% in the second year. Here is the worked example the State Board of Equalization uses:
In that example the homeowner buys a $600,000 home but is taxed as if it were worth $280,000, not $600,000. That gap is the Prop 19 benefit, and it follows you for as long as you own the home.
Who qualifies for the Prop 19 base transfer?
Homeowners who are 55 or older, along with people who are severely and permanently disabled and victims of a wildfire or natural disaster. The home you sell must have been your primary residence, and the home you buy must become your primary residence.
Can I move anywhere in California and still keep my base?
Yes. Prop 19 allows the transfer to a replacement primary residence anywhere in the state. The old county-to-county limits that existed under the earlier rules were removed.
How many times can I use it?
Up to three times for those who qualify by age or disability. Under the prior law it was generally a one-time benefit, so this is a meaningful change for people who expect to move more than once.
How long do I have to buy the replacement home?
The replacement must be bought or newly built within two years of the sale of your original home, either before or after. The timing affects the threshold factor: 100% before or at the sale, 105% in the first year after, and 110% in the second year.
What if my new home costs more than my old one sold for?
You can still transfer your base. You simply add the amount above the adjusted threshold to your old taxable value, as shown in the worked example above. This is the biggest difference from the old rules, which effectively pushed you toward an equal or lesser value home.
What if my new home costs less than my old one sold for?
Your old taxable base transfers to the new home unchanged. You do not get an additional reduction below your existing base, but you keep the low base you already have rather than being reassessed at the new purchase price.
Does Prop 19 cover capital gains taxes too?
No. Prop 19 is a property-tax rule only. Capital gains on the sale of a primary residence are a separate matter, with their own primary-residence exclusion. Many downsizers look at both at once, which is worth walking through with your tax professional.
Is the calculator's number the exact tax I will pay?
No. It is an estimate at an approximate 1.1% rate to help you see the scale of the benefit. Your actual rate, any Mello-Roos or special assessments, and the Assessor's final determination will shape the real figure.
What paperwork is involved, and when?
The transfer is claimed with the County Assessor after the purchase, on the form the county provides for base-year value transfers. Because the two-year window and the timing factors matter, it helps to plan the sequence of your sale and purchase before you list, not after.
Can I get my own numbers in writing?
Yes. Enter your figures above and request the one-page worksheet, and you will receive a clean summary of your estimate along with a simple two-year timing calendar for your specific move.
Share your numbers and I will send a one-page worksheet of your estimate, plus the two-year timing calendar mapped to your move. If you are not sure what your home would sell for today, check the box and I will include a value analysis.
This calculator and page are general information for California homeowners and are not legal, tax, or financial advice. Jade Larney is a licensed California real estate agent (DRE 02241676) with Anvil Real Estate, not an attorney or CPA. Proposition 19 has conditions and limits that depend on your situation. Confirm any figures and eligibility with the County Assessor and your own attorney or tax professional before acting.