Enacted effective October 1, 2011 · Last verified June 26, 2026
In one sentenceRule 86 sets when the rules and their amendments take effect and which proceedings they govern — new actions and pending ones — unless the Supreme Court specifies otherwise or applying them would be unfeasible or work an injustice.
(a)In General. These rules and any amendments take effect at the time specified by the supreme court. They govern:
(1)proceedings in an action commenced after their effective date; and
(2)proceedings after that date in an action then pending unless:
(A)the supreme court specifies otherwise; or
(B)the court determines that applying them in a particular action would be unfeasible or work an injustice.
(b)October 1, 2011 Amendments. If any provision in Rules 1-86 conflicts with another law, priority in time for the purpose of section 3-2-706 is not affected by the amendments taking effect on October 1, 2011. Form 1. Summons—Official Form IN THE DISTRICT COURT OF THE ______________ JUDICIAL DISTRICT OF THE STATE OF MONTANA, IN AND FOR THE COUNTY OF ________________ A.B., Plaintiff, Civil No. . . . vs. SUMMONS C.D., Defendant. To: _____________________________________________ A lawsuit has been filed against you. Within 21 days after service of this summons on you or (42 days if you are the State of Montana, a state agency, or a state officer or employee), you must serve on the plaintiff an answer to the attached complaint or a motion under Rule 12 of the Montana Rules of Civil Procedure. Do not include the day you were served in your calculation of time. The answer or motion must be served on the plaintiff or plaintiff’s attorney, if plaintiff is represented by an attorney, whose name and address are listed above. If you fail to respond, judgment by default will be entered against you for the relief demanded in the complaint. You also must file your answer or motion with the court. Date: _______________________ CLERK OF THE DISTRICT COURT
(Seal)By: _____________________________________ Form 18. Third-Party Summons A.B., Plaintiff, vs. C.D., Defendant and Civil No. . . . Third-Party Plaintiff, THIRD-PARTY SUMMONS vs. E.F., Third-Party Defendant. To: (name the third-party defendant): A lawsuit has been filed against defendant ________________, who as third-party plaintiff is making this claim against you to pay part or all of what [he] may owe to the plaintiff _______________. Within 21 days after service of this summons on you (not counting the day you receive it), you must serve on the plaintiff and the defendant an answer to the attached third-party complaint, or a motion under Rule 12 of the Montana Rules of Civil Procedure. The answer or motion must be served on the defendant’s attorney, __________________, whose address is _____________________; and also on the plaintiff’s attorney, _________________, whose address is _______________________. If you fail to do so, judgment by default will be entered against you for the relief demanded in the third-party complaint. You also must file the answer or motion with the court and serve it on any other parties. A copy of the plaintiff’s complaint is also attached. You may—but are not required to— respond to it. Date: _______________________ CLERK OF THE DISTRICT COURT
(Seal)By: _____________________________________ Form 18-A. Notice of a Lawsuit and Request to Acknowledge and Waive Service of a Summons A.B., Plaintiff, Civil No. . . . vs. NOTICE OF A LAWSUIT AND REQUEST TO ACKNOWLEDGE AND WAIVE SERVICE OF A C.D., Defendant. SUMMONS To: (name of defendant—or if the defendant is a corporation, partnership or association name, an officer or agent authorized to receive service): Why are you getting this? A lawsuit has been filed against you, or the entity you represent, in this court under the number shown above. A copy of the complaint is attached. This is not a summons, or an official notice from the court. It is a request that, to avoid expenses, you acknowledge and waive formal service of a summons by signing and returning the enclosed acknowledgment and waiver. To avoid these expenses, you must return the signed acknowledgment and waiver within 21 days (42 days if you are the State of Montana, a state agency, or a state officer or employee) from the date shown below, which is the date this notice was sent. Two copies of the acknowledgment and waiver are enclosed, along with a stamped, self-addressed envelope, or other prepaid means for returning one copy. You may keep the other copy. What happens next? If you return the signed acknowledgment and waiver, I will file it with the court. The action will then proceed as if you had been served on the date the waiver is filed, but no summons will be served on you and you will have 21 days from the date you sign the acknowledgment and waiver (42 days if you are the State of Montana, a state agency, or a state officer or employee sued in an official capacity) to answer the complaint. If you do not return the signed acknowledgment and waiver within the time indicated, I will arrange to have the summons and complaint served on you, and I will ask the court to require you, or the entity you represent, to pay the expenses of making service. Please read the enclosed statement about the duty to avoid unnecessary expenses. I certify that this request is being sent to you on the date below. Date: __________________ _________________________________________ Signature of the attorney or unrepresented party _________________________________________ Printed name _________________________________________ Relationship to entity or authority to receive service _________________________________________ Address ________________________________________ E-mail address _________________________________________ Telephone number Comment: Both Form 18B and the “Duty to Avoid Unnecessary Expenses of Serving a Summons” page should always accompany this form. Form 18-B. Acknowledgment and Waiver of Service of a Summons A.B., Plaintiff, Civil No. . . . vs. ACKNOWLEDGMENT AND WAIVER OF SERVICE OF A SUMMONS C.D., Defendant. To: (name of plaintiff’s attorney or the unrepresented plaintiff): I have received your request to acknowledge and waive service of a summons in this action along with a copy of the complaint, two copies of this acknowledgment and waiver form, and a prepaid means of returning one signed copy of the form to you. I, or the entity I represent, agree to save the expense of serving a summons and complaint in this case. I understand that I, or the entity I represent, will keep all defenses or objections to the lawsuit, the court’s jurisdiction, and the venue of the action, but that I waive any objections to the absence of a summons or of service. I also understand that I, or the entity I represent, must file and serve an answer or a motion under Montana Rule of Civil Procedure 12 within 21 days from the date I sign this acknowledgment and waiver form (or 42 days if I am signing on behalf of the State of Montana, a state agency, or a state officer or employee). If I fail to do so, a default judgment will be entered against me or the entity I represent. Date: __________________ _________________________________________ Signature of the attorney or unrepresented party _________________________________________ Printed name _________________________________________ Relationship to entity or authority to receive service _________________________________________ Address ________________________________________ E-mail address _________________________________________ Telephone number Duty to Avoid Unnecessary Expenses of Serving a Summons Rule 4 of the Montana Rules of Civil Procedure has a provision to avoid the unnecessary expenses of serving a summons and complaint. A defendant who fails to return a signed acknowledgment and waiver of service requested by a plaintiff will be required to pay the expenses of service, unless the defendant shows good cause for the failure. “Good cause” does not include a belief that the lawsuit is groundless, or that it has been brought in an improper venue, or that the court has no jurisdiction over this matter or over the defendant or the defendant’s property. If the acknowledgment and waiver is signed and returned, you can still make these and all other defenses and objections, but you cannot object to the absence of a summons or of service. If you waive service, then you must, within the time specified on the acknowledgment and waiver form, serve an answer or a motion under Rule 12 on the plaintiff and file a copy with the court.
Plain-English Summary
Rule 86 handles the rules' own timing. The rules and any amendments take effect when the Supreme Court specifies, and they govern proceedings in actions commenced after the effective date and proceedings after that date in already-pending actions — unless the Supreme Court provides otherwise or the court finds that applying them in a particular case would be unfeasible or work an injustice. The rule also includes a note preserving statutory priority-in-time rules with respect to the October 1, 2011 amendments.
Frequently Asked Questions
Do rule amendments apply to cases already pending?
Generally yes — amendments govern proceedings after their effective date in pending actions, unless the Supreme Court specifies otherwise or the court determines that applying them would be unfeasible or work an injustice.
Source & verification. Reproduced verbatim from the Montana Code Annotated as
published by the State Law Library of Montana and the Montana Legislature. This rule has not been amended since its adoption.
Adopted by the Supreme Court of Montana (AF 07-0157). Last verified June 26, 2026. ·
Official text