Interrogatories are written questions one party sends another in federal civil litigation, and the answers come back in writing, under oath. They are a workhorse discovery tool: cheaper than a deposition, useful for pinning down facts, witnesses, and documents early. But federal court does not let a party send an unlimited set. Federal Rule of Civil Procedure 33 draws a hard default line at 25, and the way courts count subparts is where most disputes start.
This guide explains the cap in Rule 33(a)(1), how judges decide whether a subpart counts as its own interrogatory, the 30-day answer deadline in Rule 33(b)(2), and what to do when 25 questions are not enough.
The 25-Interrogatory Cap: Per Party, Not Per Case
Rule 33(a)(1) states the rule plainly: “Unless otherwise stipulated or ordered by the court, a party may serve on any other party no more than 25 written interrogatories, including all discrete subparts.” Three parts of that sentence do real work.
First, the limit runs party to party. If a case has two defendants, the plaintiff may serve up to 25 interrogatories on each defendant, not 25 split between them. The flip side is equally real: each defendant may serve 25 on the plaintiff, so a plaintiff facing several opponents can receive several sets of 25.
Second, the cap is a default, not an absolute ceiling. The parties can agree to a higher number by stipulation under Rule 29, or the court can order a higher number. Many scheduling orders under Rule 16(b) set a custom interrogatory limit for the case, and that order controls over the default.
Third, leave to serve additional interrogatories “may be granted to the extent consistent with Rule 26(b)(1) and (2).” In practice, that means proportionality: the court asks whether the extra questions are relevant to a claim or defense and proportional to the needs of the case, considering the importance of the issues, the amount in controversy, access to information, resources, and whether the burden outweighs the likely benefit. A request for 40 more questions to chase a minor point will fail that test. A request for 10 more in a document-heavy commercial case, where each question targets a distinct category of records, stands a much better chance.
How Courts Count Discrete Subparts
The phrase “including all discrete subparts” exists to stop a numbering trick. Without it, a party could label 100 questions as “Interrogatory No. 1” with subparts (a) through (zz) and claim to have served only one interrogatory. The Advisory Committee Notes to Rule 33 say parties cannot evade the limit by joining as subparts questions that seek information about discrete, separate subjects.
Courts generally apply a practical test: can the subpart be answered independently, on a separate subject, without reference to the main question? If yes, it counts separately. If the subpart is factually subsumed within and necessarily related to the main question, it counts as part of that one interrogatory.
Two examples show the line:
- Counts as one. “Identify each communication between you and Supplier X concerning the contract, stating for each the date, the persons present, and the substance.” The date, persons, and substance details are all part of the same inquiry into those communications. The Advisory Committee Notes treat exactly this kind of question as a single interrogatory.
- Counts as several. “State (a) every defect you claim in the product, (b) every warning you claim should have been given, (c) every person who tested the product, and (d) your total damages.” Each subpart asks about a separate subject that could stand alone as its own interrogatory. Most courts would count that as four, not one.
Numbering choices do not change the count. Calling something “Interrogatory 1(a)” instead of “Interrogatory 2” makes no difference if the content is a discrete subject. When a receiving party believes the set exceeds 25, the usual response is a specific objection identifying the excess interrogatories, followed by answers to the first 25, and a meet-and-confer or motion if the serving party disagrees. Objecting without identifying which questions are excess, or refusing to answer anything at all, tends to fare badly.
Worked Example: Counting a Set to 25
Suppose a plaintiff serves a set numbered 1 through 18, but several items carry subparts. Counting it properly means counting subjects, not numbers:
- Interrogatories 1 to 10 are single-subject questions: 10.
- Interrogatory 11 asks about three separate contracts, one subpart each: 3, bringing the total to 13.
- Interrogatory 12 asks for the date, author, and recipients of each memo about a single meeting: 1, total 14.
- Interrogatories 13 to 18 each ask two discrete things (for example, a fact question plus a damages question): 12, total 26.
That set is one over the limit even though it is numbered only to 18. The responding party could object to the 26th interrogatory and answer the first 25. Drafting with this counting method in mind, before service, avoids the objection entirely. A good habit is to draft the set, count subjects, and cut or combine before sending, rather than discovering the overage in an objection letter.
The 30-Day Answer Deadline
Rule 33(b)(2) requires the responding party to serve its answers and any objections “within 30 days after being served with the interrogatories.” A shorter or longer time may be set by stipulation under Rule 29 or ordered by the court, and a scheduling order often adjusts the period. Absent such an adjustment, 30 calendar days is the clock.
Counting follows Rule 6(a)(1): exclude the day of service, count every intermediate day including Saturdays, Sundays, and legal holidays, and if the last day falls on a Saturday, Sunday, or legal holiday, the period runs to the next business day.
Example 1. Interrogatories are served on Monday, November 2, 2026. Exclude November 2. Day 1 is November 3, and day 30 is Wednesday, December 2, 2026. Answers and objections are due December 2.
Example 2. Interrogatories are served on Friday, October 30, 2026. Day 30 falls on Sunday, November 29, 2026, so under Rule 6(a)(1)(C) the deadline rolls forward to Monday, November 30, 2026. If you are unsure about a deadline in a live case, verify it on our federal court deadlines calculator or the free legal deadline calculator before relying on it.
Missing the 30 days has a specific cost. Rule 33(b)(4) requires objections to state their grounds with specificity, and any ground not stated in a timely objection is waived unless the court, for good cause, excuses the failure. Late, boilerplate objections are the fastest way to lose an objection that might have succeeded on time.
Getting Leave for More Than 25
When 25 genuinely will not cover the case, ask early and ask with specifics. A motion that says “this case is complex” rarely persuades. A motion that lists the additional interrogatories, explains what distinct information each one seeks, and shows why depositions or document requests cannot substitute for them gives the court something to grant.
Timing matters. Ask before serving the excess set, not after the objection arrives. Courts are more receptive to a planned request in a scheduling conference than to a retroactive request to bless questions already served over an objection. If the other side agrees, a Rule 29 stipulation is faster than a motion and avoids the fight altogether.
Also remember that interrogatories are only one discovery device. A question that would burn several interrogatories might be answered more efficiently by a deposition, where follow-up questions are unlimited, or by a document request. Our federal deposition notice guide explains how much notice Rule 30 requires before a deposition, and expert-related questions often belong with federal expert disclosure deadlines rather than in a general interrogatory set. And when a fact is already established, a request for admission can lock it in without spending an interrogatory at all — our federal request for admission deadline guide explains the 30-day response clock under FRCP 36 and the deemed-admitted consequence of staying silent.
Answering Properly: Separate, Full, and Under Oath
Rule 33(b)(3) requires each interrogatory to be answered, to the extent it is not objected to, separately and fully in writing under oath. “Separately” means an answer for each question, not a narrative that gestures at several questions at once. “Fully” means a reasonably diligent search of the party’s records and information, not only what the answering person happens to remember. For a corporation, partnership, association, or government agency, Rule 33(b)(1)(B) requires an officer or agent to answer and furnish the information available to the organization as a whole.
The person who makes the answers must sign them, and the attorney who objects must sign any objections, under Rule 33(b)(5). Because answers are under oath, they can be used at trial to the extent allowed by the Federal Rules of Evidence under Rule 33(c). Sloppy answers do not stay in discovery; they can surface in front of a jury.
One more scope point: an interrogatory is not objectionable merely because it asks for an opinion or a contention relating to fact or the application of law to fact, under Rule 33(a)(2). The court may, however, order that a contention interrogatory need not be answered until designated discovery is complete or until a pretrial conference. If you receive a contention interrogatory early, seeking deferral is usually a stronger move than a flat refusal.
Common Mistakes That Waste the Limit
First, drafting 25 long, multi-subject questions and expecting them to count as 25. They will not. Second, spending questions on information already disclosed under Rule 26(a) initial disclosures or readily available in documents the other side already produced. Third, serving a second set without checking whether the first set already used the full 25; the limit is cumulative per party, not per set. Fourth, objecting late or in general terms and thereby waiving a valid objection under Rule 33(b)(4). Fifth, answering with “see documents” without satisfying the business-records option in Rule 33(d), which has its own conditions about specifying records in sufficient detail and giving a reasonable opportunity to examine them.
Frequently Asked Questions
Does the 25-interrogatory limit apply per party or per side?
Per party. Each party may serve up to 25 interrogatories on any other party. In a multi-defendant case, a plaintiff may serve 25 on each defendant, and each defendant may serve 25 back on the plaintiff.
Do subparts always count as separate interrogatories?
No. A subpart counts separately only if it asks about a discrete, separate subject. Details that are part of the same inquiry, such as the date, persons present, and contents of a particular type of communication, generally count as one interrogatory.
What happens if the other side serves more than 25?
Object specifically to the excess interrogatories, identify which ones exceed the limit, and answer the first 25. If the parties cannot resolve it, the serving party must seek leave of court for the additional questions, and the dispute is resolved under Rule 26(b) proportionality.
When are interrogatory answers due in federal court?
Within 30 days after service, under Rule 33(b)(2), unless a stipulation or court order sets a different time. Count under Rule 6(a)(1): exclude the service day, count every day, and roll forward if day 30 falls on a weekend or legal holiday.
Can I refuse to answer a contention interrogatory?
Not merely because it asks for an opinion or contention. Rule 33(a)(2) permits such questions. You may ask the court to defer the answer until designated discovery is complete or until a pretrial conference, and you may object on other specific grounds such as privilege or proportionality.
Do state courts use the same 25-interrogatory limit?
Not necessarily. The 25 limit is a federal rule. State courts set their own limits, which vary widely, and some states use form interrogatories with different counting rules. Always check the rules of the court where your case is pending.
This article is general information only and is not legal advice. Court rules, scheduling orders, and local rules can change deadlines and limits in a specific case. Confirm the current rule and any applicable court order before acting on a deadline.