(a) Compulsory Counterclaims. A pleading shall state as a counterclaim any claim which at the time of serving the pleader has against any opposing party, if it arises out of the transaction or occurrence that is the subject matter of the opposing party's claim and does not require for its adjudication the presence of third parties over whom the court cannot acquire jurisdiction.
Rule 10.Counterclaims, Cross-claims and Third-Party Claims
Group III: Pleadings and Motions · Last amended January 1, 2018 · Last verified July 14, 2026
In one sentenceRule 10 governs counterclaims, cross-claims, and third-party claims, distinguishing compulsory from permissive counterclaims, allowing cross-claims arising from the same transaction, and setting a 30-day deadline after the Answer for bringing in a third party.
Full Text of Rule 10
(b) Permissive Counterclaims. A pleading may state as a counterclaim against an opposing party any claim that is not compulsory so long as a right of action existed thereon at the time of the filing of the complaint.
(c) A pleading may state as a cross-claim any claim by one party against a co-party which arises out of the transaction or occurrence that is the subject matter of the original action or of a counterclaim therein.
(d) Unless otherwise provided by law, whenever a third party may be liable to a defendant in any pending action for any of the plaintiff's claim against said defendant, or if said defendant may have a claim against a third party depending upon the determination of an issue or issues in said pending action, said defendant may bring an action against said third party and, unless otherwise ordered on motion of any party, such action will be consolidated for trial with the pending action or, if justice requires, said third party may be made a party to the pending action, for the purpose of being bound by the determination of any common issues. However, except for good cause shown to prevent injustice and upon such terms as the court may order, no such action will be consolidated with or said third party joined in said pending action, unless suit is brought against said third party within 30 days following filing of the defendant's Answer in said pending action.
(e) A third party against whom an action is brought in accordance with this rule and a plaintiff against whom a counterclaim has been filed may, under the same circumstances prescribed by this rule, use the same procedure with respect to another person and the same time limitation shall apply, except that as to a plaintiff the 30 days will begin to run on the date the counterclaim is filed.
(f) This rule shall not be construed to limit or abridge in any way the existing common law practice of joining parties in pending actions whenever justice and convenience require, or the giving of notice to third parties to come in and defend any pending action or be bound by the outcome thereof.
(g) This rule does not apply to a defendant who contends that a third party is solely liable to the plaintiff or to a defendant in a tort action as to a possible joint tortfeasor against whom said defendant has no right to contribution or reimbursement.
(h) For convenience, to avoid prejudice, or to expedite and economize, the court may order a separate trial of one or more separate issues, claims, crossclaims, counterclaims or third-party claims.
Amendment History
Adopted May 22, 2013, eff. October 1, 2013; amended October 18, 2017, eff. January 1, 2018.
2017: The 2017 amendment added subsection heading in (a); added (b) and (h); and redesignated former (b) through (f) as (c) through (g).
Plain-English Summary
Rule 10(a) makes some counterclaims mandatory: a party must state as a counterclaim any claim it has against an opposing party at the time of serving its pleading, if that claim arises from the same transaction or occurrence as the opposing party's claim and does not require third parties the court cannot reach. Rule 10(b) then allows permissive counterclaims — claims that do not meet that same-transaction test but on which a right of action existed when the complaint was filed. Rule 10(c) permits cross-claims between co-parties arising from the same transaction or occurrence at issue in the original action or an existing counterclaim.
Rules 10(d) and (e) address bringing in a third party who may be liable to a defendant for the plaintiff's claim, or against whom the defendant has a dependent claim. The defendant may bring a third-party action, which will ordinarily be consolidated for trial with the pending case or, if justice requires, the third party may be joined directly. The rule sets a firm 30-day deadline, running from the filing of the defendant's Answer, for bringing such an action or joining the third party — extendable only for good cause shown to prevent injustice. A third party brought in this way, or a plaintiff facing a counterclaim, can use the same procedure against another person, with the same 30-day clock, except that for a plaintiff the 30 days runs from the filing of the counterclaim.
Rules 10(f) and (g) mark the edges of this rule: it does not limit the existing common-law practice of joining parties or giving notice to third parties to defend or be bound, and it does not apply where a defendant claims a third party is solely liable to the plaintiff, or in tort cases involving a joint tortfeasor against whom the defendant has no right to contribution or reimbursement. Rule 10(h), added in 2017, gives the court authority to order separate trials of individual issues, claims, cross-claims, counterclaims, or third-party claims for convenience, to avoid prejudice, or to expedite and economize the proceedings.
Frequently Asked Questions
What makes a counterclaim compulsory rather than permissive?
Under Rule 10(a), a counterclaim is compulsory if it arises out of the same transaction or occurrence as the opposing party's claim and does not require the presence of third parties the court cannot get jurisdiction over. Rule 10(b) allows other claims to be brought permissively even without that connection, so long as a right of action existed when the complaint was filed.
How long does a defendant have to bring in a third party after filing an Answer?
Rule 10(d) sets a 30-day deadline from the filing of the defendant's Answer for suing the third party or having the third party joined, unless the court excuses a late filing for good cause shown to prevent injustice.
Can I bring a cross-claim against a co-defendant, not just against the plaintiff?
Yes. Rule 10(c) allows a cross-claim against a co-party when it arises out of the same transaction or occurrence as the original action or an existing counterclaim.
Does Rule 10 apply if I just think someone else, not me, is entirely responsible to the plaintiff?
No. Rule 10(g) excludes that situation, along with a tort defendant's claim against a joint tortfeasor for whom there is no right of contribution or reimbursement, from this rule's third-party procedure.
Can the court order separate trials for different claims in the same case?
Yes. Rule 10(h) allows the court to order a separate trial of one or more issues, claims, cross-claims, counterclaims, or third-party claims for convenience, to avoid prejudice, or to expedite and economize the proceedings.
Source & verification. Rule text, official Comments, and amendment
history are reproduced verbatim from the New Hampshire Superior Court Civil Rules, adopted
by the New Hampshire Supreme Court. Last verified July 14, 2026.
· Official source
Also known as: nh compulsory counterclaim rulethird party complaint deadline nhcross claim nh superior courtpermissive counterclaim nhjoint tortfeasor contribution nh rule 10