When Are Interrogatory Responses Due in California?

Not legal advice. Core CCP rules checked against Westlaw (via CoCounsel legal research) on July 24, 2026. County local rules are paraphrased summaries; individual department standing orders are NOT included. Verify every date against the operative code sections and your court’s rules before relying on it.

Responses to interrogatories are due 30 days after service. Code of Civil Procedure section 2030.260 sets that clock, and it starts on the day the interrogatories are served, not the day you receive them or the day you first read them.

The 30 days is only the starting point. How the discovery was served changes the real due date, and this is where calendaring mistakes happen.

Service extensions that change your due date

If the interrogatories were served electronically, add 2 court days (CCP section 1010.6). Served by mail within California, add 5 calendar days. Mail from outside California but inside the US, add 10. Mail from outside the country, add 20 (CCP section 1013). Express mail or overnight delivery adds 2 court days. Personal service adds nothing.

Then one more rule: if the final day lands on a weekend or a court holiday, the deadline rolls forward to the next court day (CCP section 12a). California courts observe holidays most people forget about, including Lincoln’s Birthday in February and Native American Day in September, so a deadline that looks fine on a regular calendar can move.

Our calculator stacks all of this for you. Enter the service date and method, get the real due date.

Discovery response deadline calculator FREE

What happens if you miss the deadline

You waive all objections, including attorney-client privilege and work product (CCP section 2030.290). The propounding party can move to compel and seek sanctions. Relief from waiver exists, but it requires a motion, a showing of mistake or excusable neglect, and responses in substantial compliance. Nobody wants to write that motion.

FAQ

Can the parties agree to extend the deadline?

Yes. CCP section 2030.270 allows a written agreement extending the time. Get it in writing, and confirm the agreement preserves objections.

Do the responses need to be verified?

Yes, unless the responses contain only objections. An unverified response to interrogatories is treated like no response at all.

Does the deadline change in unlawful detainer cases?

Yes. The response period is 5 days in unlawful detainer proceedings, not 30.

This page is general legal information, not legal advice. Verify every deadline against the current code and your court’s rules.