This is an estimate for planning, from Zillow's ZIP-wide typical values applied to your purchase price. It is not an appraisal, a broker price opinion, an offer, a loan offer, or tax or legal advice, and Rudy is a real estate agent, not a lender, appraiser or tax professional.
How the estimate works
- Zillow's typical value for your home type in 92118 is read for your purchase month and for the latest month.
- That change is applied to the price you paid, and the condition you select shapes the range.
- A loan you still pay is reduced by standard fixed-rate payments, starting the month after you bought, to estimate what remains.
- Equity is the midpoint less that balance; the net subtracts selling costs as well, before tax.
- The Prop 13 estimate grows your purchase price with the Board of Equalization's inflation factor for every tax year, no more than 2%.
Your Prop 13 value and Prop 19
Island homes are taxed on their Prop 13 value, which begins with the sale price and grows by 2% or less each year. Long-time Coronado owners often find that value far below what the home would bring today.
Proposition 19 can help owners 55 or older who leave the island for another California home: the taxable value may come along when that home is purchased inside two years of the sale, for as many as three moves. The assessor confirms who qualifies.
Island owners often turn to the downsizing calculator and Prop 13 since 1978: a Coronado timeline.
Sources and dates
- Zillow Research, Zillow Home Value Index (ZHVI) by ZIP code: all homes, single-family and condo; middle tier, smoothed and seasonally adjusted (data through September 2026, files updated Oct 16, 2026)
- FHFA House Price Index for five-digit ZIP codes (annual, developmental index, not seasonally adjusted; 2000 = 100), used only for purchases before Zillow's series begin. Citation: Bogin, Doerner and Larson, Local House Price Dynamics: New Indices and Stylized Facts, FHFA Working Paper 16-01 (annual, through 2025)
- Freddie Mac Primary Mortgage Market Survey (PMMS): weekly 30-year and 15-year fixed averages; the page uses the mean for your purchase month (monthly means through October 2026; latest weekly 30-year average 7.24% on Oct 29, 2026)
- California State Board of Equalization, Letter To Assessors No. 2026/002: inflation factors for 1976-77 through 2026-27, with Revenue and Taxation Code section 51 and California Constitution article XIII A, section 2(b) (January 13, 2026)
- California State Board of Equalization, Proposition 19 (checked Oct 30, 2026)
- Assumptions, not sourced figures: the condition range (the same rule of thumb as the home value range tool), 6% selling costs, 20% down, regular payments on a fixed-rate loan starting the month after you bought, and the first inflation factor applying on the first January 1 after your purchase
Questions owners ask
How close is a ZIP estimate for an island home?
Close in direction, looser in amount. A bay view, a corner lot or a rebuild can put your home well outside the range. Rudy's free review of recent Coronado sales gives a number you can lean on.
Why the ZIP code and not my block?
Zillow's ZIP figures come out every month and reach back to 2000, a steady way to measure change since you bought. Your block shows up in comparable sales.
I refinanced. Which loan option fits?
The second one. Enter what you owe today on every loan against the home, including any line of credit, and the page uses it.
Is my Prop 13 value what the home is worth?
No. It is the value the county taxes, which can rise from your price by 2% a year at most. Market value on the island is usually much higher, and your tax bill lists the exact taxable value.
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