What is an exchange of information in a California assessment appeal?

An exchange of information is a pre-hearing discovery tool under Cal. Rev. & Tax. Code §1606. It forces both sides to disclose the basis of their opinion of value before the Assessment Appeals Board hearing, so neither party is ambushed.

How it works:

• Who can initiate: When the assessed value is $100,000 or less, only the applicant may request an exchange. When it exceeds $100,000, either the applicant or the assessor may request one.
• What you disclose: Each side states the basis of its value opinion. For a comparable-sales approach, you must identify each comparable property with enough certainty — assessor's parcel number, street address or legal description, approximate sale date, zoning, price paid, and terms of sale.
• Timing: A request may accompany the BOE-305-AH application or be filed any time up to 30 days before the hearing.
• At the hearing: If you initiated an exchange, you generally may introduce only the evidence and comparables you disclosed — but you can rebut new matter the assessor raises. This is why the exchange is strategic: it locks in the assessor's comps and prevents surprises.

For most homeowners with assessments above $100,000 (common in California), an exchange of information is worth requesting: it reveals the assessor's comparable sales early so you can prepare rebuttals. The state BOE assessment appeals page and Publication 30 describe the procedure, and §1606 is the controlling statute.