Why the assessor's value and the estimate differ

How the assessed value is set

• Property is valued at its 1975 market value or, after that, its value when it changed ownership or was newly built. That is the base year value.
• Each year the value can rise with inflation, but by no more than 2%.
• It is reappraised only when ownership changes, new construction is completed, or the market value falls below the assessed value.
• The tax rate is 1% of assessed value plus any voter-approved bonds.
• When market value drops below the assessed value, the assessor can lower it temporarily under Proposition 8. Those values can move by any amount but never above the Proposition 13 value.

Why the gap is often wide on country property

• Long ownership. Land held for decades keeps an old base year value, so its assessed value can sit far below what it would sell for.
• Williamson Act contracts. Contracted land is assessed on its use, not its market value. See Williamson Act land.
• Additions. New construction adds the value of what was built, not a fresh appraisal of the whole property.

When the assessed value is higher

A recent purchase or new construction sets the assessed value at that time's price. If prices have eased since, or the estimate misses something the records don't show, the assessed value can sit above the estimate. A land specialist's walk-through settles that.

Where each number on Cornload comes from

The assessor value comes from the county assessor roll. The Cornload Estimate comes from recent sales of homes on an acre or more; here's why we don't use tract-home sales.