For a California property owner, the assessed value carried over from a decades-ago purchase is frequently worth more, in cash flow terms, than the appreciation in market value itself. A 1978 base-year value reassessed today can multiply the annual tax bill by ten or fifteen times. Preserving that base-year value—across sales, gifts, trust transfers, divorces, and inheritances—is the central work of a Proposition 13 practice.
We have advised California property owners on assessment, exclusion, and appeal questions for more than four decades. Our practice covers single-family homes held in long-standing family trusts, multi-property portfolios owned through partnerships and LLCs, and operating real estate held inside closely held businesses. The analysis differs in each setting, but the goal is consistent: keep the base year wherever the law allows, and avoid the accidental transfer that triggers a reassessment.
The change-in-ownership rules
Proposition 13 limits annual increases in assessed value, but every change in ownership triggers a reassessment to current market value unless an exclusion applies. The change-in-ownership rules are deceptively complex. A direct deed from parent to child is one event; a transfer of LLC membership interests representing the same property is treated very differently. A gift into an irrevocable trust may or may not trigger reassessment depending on the trust's beneficial interests and the retained powers of the grantor.
The California State Board of Equalization, the county assessors, and the Office of Tax Appeals have generated decades of guidance on what constitutes a change in ownership, what qualifies as an exclusion, and how aggregations of small transfers can—or cannot—be combined. Reading that guidance correctly is essential to any planning involving California real estate.
Proposition 19 and the parent-child exclusion
The 2020 passage of Proposition 19 narrowed the parent-child exclusion substantially. The pre-2021 rule allowed a parent to transfer a primary residence of any value plus an additional one million dollars of assessed value of other real property to a child without reassessment. The current rule limits the exclusion to a primary residence the child will occupy as a primary residence within one year, with a value cap tied to the existing base value plus one million dollars. Investment properties, second homes, and commercial parcels no longer qualify for the exclusion at all.
For families that did not complete intergenerational transfers before the February 2021 deadline, the new framework has fundamentally changed estate planning. Strategies that once preserved base-year values across multiple properties now apply to a single residence, and many families have rebuilt their plans around lifetime gifting, partnership restructurings, and outright sales rather than relying on an exclusion that no longer exists.
Entity transfers and the proportional-interest rule
Real estate held through partnerships and LLCs sits under a different regime. A change in ownership occurs when any single person or entity obtains more than fifty percent of the ownership interests in a legal entity that owns California real estate, or when more than fifty percent of the original interests have changed hands cumulatively since the entity acquired the property. The cumulative rule is what catches most clients: a series of small transfers, each individually non-reportable, can in aggregate trigger reassessment of every parcel the entity owns.
We routinely audit family LLC and partnership structures for hidden proportional-interest exposure, particularly where membership interests have moved through gifts, trust funding, or buyouts of departed members. The remediation, where possible, involves restructuring before the next planned transfer rather than after.
Assessment appeals and value disputes
Where reassessment has occurred—correctly or otherwise—we represent owners before county assessment appeals boards. The case typically turns on whether a change in ownership actually occurred, on whether the assessor's valuation reflects current market conditions, and on the correct application of any available exclusions. These hearings are technical and evidentiary, and the deadlines are short. Owners who wait to consult counsel after receiving a Notice of Supplemental Assessment frequently discover that the appeal window has already narrowed.
Planning for the next generation
Most of our Proposition 13 work is anticipatory. We sit with families, catalog every California parcel and its base-year value, identify the children who will occupy a residence and those who will not, and design a transfer plan that preserves what the law still allows. The plan often combines a Prop 19 transfer of the primary residence to one child, a sale-or-exchange of investment property at a coordinated time, and the use of long-term irrevocable structures for parcels the family intends to hold indefinitely.
A Coachella Valley family held five income properties through a long-standing limited partnership. Two of the original three general partners had passed away, and successor trustee transfers had quietly accumulated past the cumulative fifty-percent threshold. We restructured the partnership ahead of a planned sale, documented the remaining transfers under available exclusions, and avoided reassessment on four of the five parcels. The fifth was sold and replaced through a §1031 exchange.
If you own California property and have not had your base-year exposure reviewed since Proposition 19 took effect, the time to do so is now. Many of the most valuable strategies depend on acting before, not after, a planned change in ownership.