Wondering whether passing your home to your kids will reset its property taxes? This calculator applies California's Proposition 19 parent-child rules to estimate the new assessed base and annual tax.
How Prop 19 changes what your kids inherit
When California voters passed Proposition 19 (effective February 16, 2021), they replaced the old, generous Proposition 58 parent-child exclusion with a far narrower rule. Under the prior law, a parent could transfer a home of nearly any value to a child and the child kept the parent's low Proposition 13 assessed value — no reassessment, often a tiny tax bill on a property worth ten times its assessed value. Prop 19 ended that for most transfers.
Today, the parent-child exclusion only applies when the child moves into the home as their own primary residence, and even then the protection is capped. If the child uses the home as a rental, a vacation home, or simply keeps it vacant, the county reassesses the property to current fair-market value — which in Simi Valley and most of Ventura County means a dramatically higher tax bill.
Estimate only. Not legal, tax, or financial advice — confirm with the appropriate professional.
The math behind the calculator
The exclusion shelters the old assessed value plus $1,000,000 of additional market value (the cap is indexed and adjusts over time; this tool uses the round $1,000,000 figure). Here is the logic, step by step:
- Not a primary residence? The home is fully reassessed. The new taxable base equals current fair-market value, period.
- Primary residence, value within the cap? If fair-market value is at or below the old assessed value plus $1,000,000, the original assessed base transfers unchanged — the child keeps the parent's low Prop 13 basis.
- Primary residence, value above the cap? The new base equals fair-market value minus $1,000,000. The child gets partial protection, but not full.
We estimate annual tax at roughly 1.1% of the assessed base. Your real bill depends on the exact 1% Prop 13 rate plus local voter-approved bonds and any Mello-Roos / CFD assessments, which the calculator does not include.
Why this matters so much in Ventura County
Consider a parent who bought a Simi Valley home decades ago with an assessed value of $300,000 that is now worth $850,000. If a child moves in as their primary residence, the difference between FMV ($850,000) and old base ($300,000) is $550,000 — comfortably under the $1,000,000 cap — so the child keeps the $300,000 base and a tax bill near $3,300 a year. But if that same child rents the property out, it reassesses to $850,000, and the annual tax jumps to roughly $9,350. That swing — thousands of dollars every year — is exactly what families need to plan around before a transfer happens.
Timing, titling, trust structure, and the order of events can all change the result. Some families benefit from acting before a transfer; others discover that a planned strategy triggers reassessment they did not expect. This is squarely a job for an estate-planning attorney and a CPA, but the calculator gives you a realistic starting estimate so the professional conversation is productive.
Important limits of this estimate
- It does not account for the indexing adjustments to the $1,000,000 cap, which rises over time.
- It assumes a clean parent-to-child transfer of a single qualifying property; grandparent-grandchild and multi-owner situations have additional rules.
- It excludes Mello-Roos, CFDs, special assessments, and local bond rates that push effective tax above 1.1%.
- It is not a substitute for advice from a licensed California attorney, CPA, or the Ventura County Assessor's office.
Frequently Asked Questions
Does Prop 19 reassess a home if my child moves in?
Not necessarily. If your child makes the inherited home their primary residence and the property's fair-market value is no more than $1,000,000 above your old assessed value, the original Prop 13 base transfers and there is no reassessment. Above that $1,000,000 cap, only the excess is added to the new base.
What happens if my child rents out the inherited home?
The parent-child exclusion does not apply to a property that is not the child's primary residence. The county reassesses the home to current fair-market value, which in Ventura County usually means a much larger annual property tax bill.
Is the $1,000,000 exclusion amount fixed?
No. The cap is indexed and adjusts over time. This calculator uses the round $1,000,000 figure for clarity; confirm the current adjusted amount with the California State Board of Equalization or your county assessor.
Should I rely on this calculator for estate planning?
No. It is an educational estimate only. Prop 19 outcomes depend on titling, trusts, timing, and exact local tax rates. Always confirm your plan with a licensed estate-planning attorney and a CPA before transferring property.
