Agriculture · Glossary

Williamson Act

Updated 2026-07-18

Williamson Act is California's program allowing local governments to contract with landowners to restrict land to agricultural or compatible open-space uses in exchange for property-tax assessment based on restricted use. A contract can constrain development and usually continues until nonrenewal, cancellation, or another lawful termination process is completed.

What it means

Contracts generally renew automatically each year for a rolling term unless a notice of nonrenewal is filed. Farmland Security Zone contracts use longer terms.

Why it matters for land decisions

Contract status affects allowable use, valuation, subdivision, and development timing.

  • Obtain the recorded contract and map.
  • Confirm status with the county program administrator.

People also ask

Does a sale end a Williamson Act contract?

No. The restriction generally runs with the land and binds successors.

Can a Williamson Act contract be cancelled immediately?

Cancellation is a discretionary process requiring statutory findings and fees; nonrenewal is a separate phased expiration process.

Official sources

Related terms

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