The first thing you can do with your assessor parcel number, or APN, is look up your own property on your county assessor’s website. Every county in California assigns this number to each parcel of land. It is like a fingerprint for your property. You can find it on your most recent property tax bill. Once you type that number into the county site, you can see the assessed value of your home and the tax rate applied to it.

Many people do not realize that their property tax in California does not follow the market value of their house. It follows a base year value set by Proposition 13. That base year value is the value of the property at the time you bought it, plus a small annual increase of no more than two percent. This is why two identical houses on the same street can pay very different tax bills. One house was bought decades ago, so its base year value is low. The other was bought last year, so its base year value is close to today’s market price.

A common question is what happens when you sell your home. After a sale, the base year value resets to the sale price. This means the new owner will pay taxes based on that new price. The old owner’s base year value does not carry over. The county sends a supplemental tax bill a few months after the sale. This bill covers the difference between the old assessment and the new one for the rest of the tax year. The amount can be a surprise if you do not plan for it.

Another question people ask is about inheriting a home. The rules for inheritance changed in recent years. If you inherit a home from a parent, you might be able to keep the parent’s lower base year value, but only under certain conditions. You must use the home as your primary residence. The old rules that people assumed would apply no longer work the same way. Reading the current rule before you make any plans is the cheap step. It can save you from a big tax jump later.

People also wonder if they can appeal their assessed value. You can, but only if you think the assessor made a mistake about your property’s characteristics or used the wrong base year. You cannot appeal just because the market dropped. Proposition 13 locks in your base year value, and that is what determines your tax. If you bought your home recently and the market falls, your tax stays based on your purchase price. That is the trade-off for the stability the system gives you.

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