Understanding Prop 13: What Every California Homeowner Should Know About Property Taxes

If you own a home in California, Proposition 13 shapes your property tax bill more than almost any other factor. Passed by voters in 1978, it has protected homeowners from runaway tax increases for decades, and it still plays a major role in how much you pay and how much a future buyer will pay when you sell. Here is what it does and why it matters.

What Prop 13 Actually Does

Prop 13 sets your property’s assessed value at its purchase price and caps how fast that assessed value can rise. Instead of your taxes jumping every time the market climbs, the assessed value can only increase by a maximum of two percent per year, regardless of how much the home appreciates. Your base property tax rate is limited to one percent of that assessed value, plus any local voter-approved bonds and assessments.

Why It Matters So Much in Silicon Valley

In an area where home values have risen dramatically, the gap between a home’s market value and its Prop 13 assessed value can be enormous. A family that bought decades ago may pay a fraction of what a new buyer next door pays for a nearly identical house. That protection is one reason longtime owners can afford to stay in neighborhoods that have appreciated far beyond what they could buy into today.

What Happens When a Home Changes Hands

Here is the part buyers need to understand. When a property is sold, it is generally reassessed to its current market value, which resets the tax basis. That means your future property tax bill is based on what you pay, not on the previous owner’s low assessment. Budgeting around the current market value rather than the seller’s old tax bill will save you from a surprise.

Transfers and Inheritance

The rules around passing property to children and grandchildren changed with Proposition 19 in 2021, which narrowed the old parent-to-child exclusion. If you are planning to keep a family home in the family or you inherited property, the reassessment rules are more limited than they used to be, and the details matter.

Talk Through Your Situation

This is general information, not tax or legal advice, and everyone’s circumstances are different. If you are buying, selling, or planning how to hold a family property, I am glad to help you understand how the tax basis will affect your numbers and connect you with a tax professional when the situation calls for one. Reach out any time and we can walk through it together.