California discovery has a deadline that forgives almost nothing. If the other side serves verified responses that dodge your questions, bury you in boilerplate objections, or leave key answers half finished, you have 45 days from the service of those responses to give notice of a motion to compel further responses. Miss it, and the statute says you waive the right to compel a further response to those requests. Courts enforce that waiver strictly. There is no good-cause escape hatch in the statute, no relief for a calendaring slip, and no second bite at the same responses.
That harshness is exactly why the rule trips up so many litigants. The 45 days run from service, not from the day you read the responses. The count changes with the method of service. A supplemental response can restart the clock for the items it covers. And a verbal agreement to extend the deadline is worth nothing. Get any one of those details wrong and a motion you spent weeks preparing can be denied as untimely before the judge ever reaches the merits.
The Three Statutes Behind the Rule
The same 45-day language appears in three parallel sections of the Code of Civil Procedure, one for each kind of written discovery. Section 2030.300(c) governs interrogatories, section 2031.310(c) governs demands for inspection of documents and tangible things, and section 2033.290(c) governs requests for admission. Each one says, in substance: unless notice of the motion is given within 45 days of the service of the verified response, or any supplemental verified response, or on or before a specific later date the parties have agreed to in writing, the propounding party waives any right to compel a further response.
Three words in that sentence do most of the work. “Notice” means the motion papers must be served within the window; the hearing itself will come later, on at least 16 court days’ notice under section 1005(b). “Verified” means the clock runs from a response signed under oath, which matters when the other side serves objections without verification, as discussed below. And “service” means the date on the proof of service, not the date the responses landed in your inbox or on your desk.
Worked Example: Counting 45 Days
Suppose the other side serves verified responses to your interrogatories on Monday, November 2, 2026. Exclude the service day and count forward 45 calendar days. Day 45 lands on Thursday, December 17, 2026. That is the last day to give notice of your motion to compel further responses, assuming personal or electronic service with no extension.
Change the method of service and the answer changes. If those same responses were served by mail within California, section 1013 adds five calendar days, pushing the deadline to Tuesday, December 22, 2026. If the responses were mailed from outside California but within the United States, section 1013 adds ten days instead.
Now suppose the responses were served on Thursday, October 8, 2026. Forty-five days later is Sunday, November 22, 2026. A deadline that falls on a weekend or court holiday does not simply expire there: under section 12a, it rolls forward to the next court day, so the last day to give notice becomes Monday, November 23, 2026. The same rollover applies to court holidays, which is why you should check the court’s holiday calendar rather than assuming a federal holiday list matches. If you want a quick check on your own dates, run them through our free legal deadline calculator and then confirm the result against the statute and the proof of service.
How the Service Method Changes the Math
Everything turns on the proof of service attached to the responses, because it states both the date and the method of service. Work from that document, not from memory:
- Personal service: 45 calendar days from the service date, with a weekend or holiday rollover under section 12a if day 45 is not a court day.
- Mail within California: 45 days plus five calendar days under section 1013.
- Mail from outside California but within the United States: 45 days plus ten calendar days under section 1013.
- Electronic service: 45 days plus two court days under section 1010.6. Court days exclude weekends and court holidays, so this one requires the court calendar, not a straight count.
One common error is counting from receipt. If responses are mailed on a Monday and arrive on a Thursday, the clock still started on Monday. Another is treating the 45 days as court days. They are calendar days, and only the service-method extensions and the section 12a rollover adjust them.
When the 45-Day Rule Does Not Apply
The 45-day clock applies to motions to compel further responses, meaning the other side answered but badly. It does not apply when the other side never responded at all. If no response arrives, the motion is to compel responses under section 2030.290 (interrogatories), section 2031.300 (document demands), or section 2033.280 (requests for admission), and those sections carry no 45-day deadline. The distinction is worth getting right, because filing the wrong motion wastes the window on the right one.
Unverified responses sit in between, and California courts have given a clear answer: a response served without verification is tantamount to no response at all. That principle comes from Appleton v. Superior Court (1988) 206 Cal.App.3d 632. In practice, if the other side serves objections with no verified answers, you are usually looking at a motion to compel responses, not a further-responses motion, and the 45-day clock does not control. But do not assume the point without checking the papers. If verified answers accompany the objections, the further-responses route, and its deadline, apply to those answers.
Before You File: Two Requirements That Can Kill the Motion
Meeting the deadline is necessary, not sufficient. Two further requirements decide whether the court will even reach your arguments.
First, the meet and confer. Every further-responses statute requires the motion to be accompanied by a meet and confer declaration under section 2016.040, showing a reasonable, good-faith attempt to resolve the dispute informally, in person, by telephone, or by videoconference. A single voicemail or a two-line email rarely satisfies a judge. The declaration should describe a specific effort: a letter identifying each deficient response and why it falls short, a call or meeting to discuss it, and a deadline given for correction. Start this process the week the responses arrive, not in week six, because a genuine meet and confer takes time and the 45-day clock does not pause while you do it.
Second, the separate statement. California Rules of Court, rule 3.1345 requires a separate statement for a motion to compel further responses. For each disputed request it must set out the full text of the request, the full response including objections, and the factual and legal reasons a further response should be compelled, all complete enough that the judge need not consult any other document. A court may allow a concise outline instead, but only if it grants that permission; do not assume it. For document demands, section 2031.310(b)(1) adds one more element the other two statutes do not: the motion must set forth specific facts showing good cause for the documents sought. Budget real drafting time for the separate statement. It is routinely the longest document in the motion and the one judges rely on most.
Extending the Deadline: Only in Writing
The statutes give exactly one safe way to buy more time: a written agreement to a specific later date. If meet and confer talks are productive and the other side is working on supplemental responses, get the extension in a short written stipulation naming the new date before the 45 days expire. A phone understanding, even between lawyers who trust each other, does not protect the deadline. Neither does the other side’s promise to supplement, unless it is tied to a written date.
A supplemental verified response also resets the clock, but only for the ground it covers. If the other side serves a supplemental response to five interrogatories, you get a fresh 45 days measured from service of that supplemental response as to those five, not a new window for every response in the original set. Calendar each supplemental response separately.
There is one more clock to watch. Under section 2024.020, discovery motions must be heard on or before the 15th day before the date initially set for trial. A motion noticed inside the 45 days can still run into trouble if the hearing cannot be set before that cutoff, so reserve the hearing date early and check the trial date before you calendar anything. Our California discovery cutoff guide walks through the 30-day close-of-discovery and 15-day motion cutoffs in detail.
The Cost of Getting It Wrong
Losing the right to compel is not the only risk. Each further-responses statute provides that the court shall impose a monetary sanction against the party who unsuccessfully makes or opposes the motion, unless it finds the sanctioned party acted with substantial justification or that other circumstances make the sanction unjust. A motion filed one day late is not merely denied; it can cost the moving party the other side’s fees. That sanction exposure is a further reason to calendar conservatively: if the count is close, file early rather than arguing about the last day later.
The practical routine is simple. When verified responses arrive, note the service date and method from the proof of service the same day, compute the 45th day with the correct service extension, flag the section 12a rollover if it lands on a weekend or holiday, start the meet and confer within the week, and get any extension in writing before the window closes. If a deadline has already passed, do not file anyway and hope. Check whether a supplemental response restarted the clock, whether the responses were unverified, and whether the right motion is a responses motion with no deadline at all. And if you have already missed a deadline of any kind, our missed court deadline guide covers the broader options for damage control.
What happens if I miss the 45-day deadline?
You waive the right to compel a further response to those requests. The deficient responses stand, and the objections you wanted to challenge become effectively permanent. The statute provides no good-cause exception, so a late motion is normally denied as untimely without reaching the merits, and you risk a monetary sanction for an unsuccessful motion.
Does a supplemental response restart the 45-day clock?
Yes, for the items it covers. The statutes measure the 45 days from service of the verified response “or any supplemental verified response.” A supplemental response to five interrogatories starts a fresh 45 days for those five. It does not reopen the window for responses that were never supplemented.
Do I count from when I received the responses or when they were served?
From when they were served, as shown on the proof of service. The statutes say “within 45 days of the service of the verified response.” Mail delays do not move the start date; they are handled instead by the section 1013 extension of five or ten days, depending on where the responses were mailed from.
Does the 45-day rule apply if the other side never responded?
No. The 45-day rule governs motions to compel further responses, where an answer was given but is deficient. When no response arrives at all, the motion is to compel responses under section 2030.290, 2031.300, or 2033.280, and those sections impose no 45-day deadline. Unverified responses are treated as no responses under Appleton v. Superior Court, so the same distinction can apply there.
Can the deadline be extended by agreement?
Only by a written agreement to a specific later date. The statutes expressly allow a later date “to which the propounding party and the responding party have agreed in writing.” A verbal understanding does not count, and neither does an informal promise to supplement. Get the new date in writing before the original 45 days expire.
What if day 45 falls on a weekend or court holiday?
Under section 12a, the deadline rolls forward to the next court day. For example, verified responses served on Thursday, October 8, 2026 produce a 45th day of Sunday, November 22, 2026, so the last day to give notice becomes Monday, November 23, 2026. Check the court’s holiday calendar, since California court holidays differ from the federal list.
This article is general information about California court procedure, not legal advice for any specific case. Deadlines depend on the court, the type of case, and the method of service. If a motion deadline is close, confirm the count against the statute, the proof of service, and the court’s calendar, or speak with a California attorney promptly.