A home of $4M or more in San Diego's coastal market is financed in 2026 with a jumbo mortgage, with cash, or with a structure that combines the two. The conforming loan limit for a one-unit home in San Diego County is $1,104,000 this year — above the $832,750 national baseline, short of the $1,249,125 high-cost ceiling that Los Angeles and Orange counties carry. The market this page covers runs from La Jolla's coastline, within the City of San Diego, north through Del Mar to Rancho Santa Fe, an unincorporated county community, and across the bay to Coronado, its own small city. One structured path, The Family Office Mortgage, pairs an interest-only jumbo loan with a premium-financed indexed universal life insurance policy; its projected payout is designed to make the mortgage payments from year 16.
Why nearly every purchase here is a jumbo loan
Each year the Federal Housing Finance Agency sets the largest mortgage Fannie Mae and Freddie Mac may buy. For 2026 the baseline is $832,750 in most of the country, rising in high-cost areas to a statutory ceiling of $1,249,125. San Diego County's figure on the FHFA's 2026 county list is $1,104,000 — high-cost, but not at the ceiling. A buyer putting 20% down on a $4,500,000 home borrows $3,600,000, more than three times the county limit. There is no conforming shape that fits this market.
The prices make that concrete. Redfin's data for the three months ending September 2026 put the median sale price at about $5,277,000 in Rancho Santa Fe, up 11.7% from a year earlier; about $2,626,000 in Coronado, up 16.7%; and about $2,273,000 in La Jolla, down 6.3%. Del Mar's median over the three months ending June 2026 was about $4,473,000. These are medians across all home types; the segment this page addresses — ocean-view La Jolla, the Rancho Santa Fe Covenant, Del Mar west of the freeway, Coronado's bayside and oceanfront blocks — sits above them. Every financed purchase at $4M or more is a jumbo.
Because a jumbo cannot be sold to the two agencies, each lender keeps the loan or places it privately and writes its own terms. How an interest-only jumbo mortgage works covers the structure, including the detail that matters most in planning: the lender qualifies you on the later, fully amortizing payment.
How buyers here actually finance
Cash. San Diego draws second-home buyers and relocating households in numbers the search data shows plainly: Redfin's migration analysis for this market lists Los Angeles, San Francisco and Chicago as the leading sources of inbound buyers. A household selling in a higher-priced metro often arrives able to wire the price, and cash carries certainty with the seller. The cost is liquidity and, where raising the cash means selling appreciated assets, a capital gains tax bill that never appears on the closing statement. Paying cash versus financing works through that trade.
A jumbo sized to a large down payment. Buyers who could pay cash often borrow anyway at 40% or 50% down, keeping capital at work and cutting the interest cost. At this size the lender underwrites the whole household: documented income, reserves left after closing, sometimes pledged assets in place of liquidated ones. The calculator runs the arithmetic on any price from $4M up.
Borrowing against a portfolio. Rather than sell positions, a buyer draws on a securities-based line or pledges investment assets to the lender. The portfolio stays intact and the tax event is deferred; what is added is a variable-rate debt against marketable securities and the possibility of a maintenance call. Buy, borrow, die and where the home fits describes that route and its risks.
The local costs that change the math
Property tax. California's Proposition 13 runs the property tax on acquisition value: a change of ownership reassesses the home to the price paid, the general levy is 1% of assessed value, and afterward the assessed value generally rises no more than 2% a year, as the State Board of Equalization's overview of the system lays out. On a $4,500,000 purchase the base levy is $45,000 a year. What each address adds depends on its tax rate area — the county is divided into more than 5,000 of them — and the County Auditor and Controller's rate book for fiscal year 2025-26 publishes the totals. In most of Coronado the total is about 1.05% (roughly $47,400 on a $4,500,000 home). Most of Del Mar sits near 1.06% and most of Rancho Santa Fe — served by county agencies, its own fire protection district and the Rancho Santa Fe school districts rather than a city — near 1.07%, roughly $48,000. La Jolla pays the City of San Diego's rates, which run from about 1.03% to 1.28% across the city's tax rate areas, the most common total near 1.25% — roughly $56,300 on the same home. Treat each as an illustration: the rate follows the address, and fixed charges such as Mello-Roos come on top.
Transfer tax. San Diego County imposes a documentary transfer tax of $0.55 per $500 of consideration — $1.10 per $1,000 — under Revenue and Taxation Code section 11911 and the county ordinance the recorder's fee schedule cites. On a $4,500,000 sale the tax is $4,950, collected when the deed is recorded. Unlike the Los Angeles market, no city here adds its own layer: none of the City of San Diego, Del Mar or Coronado levies a city transfer tax, and Rancho Santa Fe, being unincorporated, has no city to levy one. Who pays is set in the purchase contract; customarily it is the seller's cost.
The deduction limit. Federal law caps the home mortgage interest deduction at interest on the first $750,000 of debt, or $375,000 if married filing separately, for loans taken out after December 15, 2017, per IRS Publication 936. On a loan of several million dollars the deduction reaches only a fraction of the interest. Your CPA can state the after-tax cost of a given loan for your case.
Where the program fits
The program is candid about where it belongs in this market. It suits a household buying a home of $4M or more, holding $5M or more in assets beyond the home and earning $500,000 or more, that intends to keep the home and would rather commit capital up front than borrow the maximum. It is a poor fit for a buyer who needs full liquidity elsewhere or expects to sell within a few years.
On a $4,500,000 home at the program's standard terms, the household commits half the price at closing: $900,000 as the down payment and $1,350,000 as the contribution to the financial instrument. The mortgage — made by a third-party lender, because the program is not a lender, bank, insurance company or government program — is $3,600,000, interest only for the first fifteen years and principal and interest for the fifteen after. The rate is an assumption for illustration, not a rate offer: at an assumed 6.5% the interest-only payment is $19,500 a month, and in years 16 to 30 the scheduled payment is $31,360 a month. The financial instrument's projected payout is sized to that payment. The payout is a projection, not a guarantee; the mortgage still runs its full thirty years; designs are tested with no growth credited in their first two years, and the instrument's values are reviewed against the plan every year.
The trade is deliberate: $2,250,000 committed at closing, in exchange for fifteen years of the lower payment and a designed source for the later ones. Whether that beats paying cash or taking a plain jumbo depends on the household, which is what the comparison and the calculator are for. The eligibility page states the criteria in full. Buyers weighing this market against coastal Los Angeles can read the Malibu market page for the same math at a different county limit.
