Exchange of expert witness information
The date for exchanging expert witness information is 50 days before the initial trial date, or 20 days after service of the demand, whichever is closer to trial. Enter the trial date and, if served, the demand date.
- CCP 2034.230(b)
- CCP 2034.220
- CCP 1013
Find the exchange date
Demand for exchange of expert witness information.
The first date set for trial.
Used to find the latest day to serve a demand.
Holidays and court closures
California judicial holidays under CCP 135 are always skipped, including Lincoln's Birthday, Cesar Chavez Day and Native American Day.
For weather or emergency closures. Check the court's notice to confirm it extends deadlines.
How the deadline is counted
- Count 50 days back from the initial trial date. If that lands on a closed day, the calculator moves earlier.
- Count 20 days after service of the demand, with any service extension.
- Use the date closer to trial. The demand should set that date for the exchange.
Worked examples
| Example | Trial date | Deadline |
|---|---|---|
| Trial date only | Mon, Mar 15, 2027 | Fri, Jan 22, 2027 |
| Demand served late, electronically | Mon, Mar 15, 2027 | Thu, Feb 11, 2027 |
When to serve the demand
A demand must be made no later than the 10th day after the initial trial date is set, or 70 days before that trial date, whichever is closer to trial (CCP 2034.220). The calculator shows the latest demand date if you enter when trial was set. A supplemental expert list may follow within 20 days after the exchange (CCP 2034.280).
Common questions
When do experts get exchanged in California?
On the date set in the demand, which must be 50 days before the initial trial date or 20 days after service of the demand, whichever is closer to trial.
Does a continued trial date reset the exchange?
Not automatically. The statute runs from the initial trial date unless the court orders otherwise.
When must the demand be served?
No later than 10 days after the initial trial date is set, or 70 days before trial, whichever is closer to trial.
Sources
- Code of Civil Procedure, sections 2034.220, 2034.230 and 2034.280
- Code of Civil Procedure, section 1013
Rules last checked October 2026. This calculator does not give legal advice. Confirm the date against the rule and any order in your case.