A motion to substitute a party plaintiff is filed under Federal Rule of Civil Procedure 25 (or its state equivalent) to replace the original plaintiff with a new one when the original has died, become incompetent, transferred their interest in the case, or left public office. The motion itself is short. The deadlines around it are not forgiving, and a missed one can end the case.
When Substitution Is Allowed
Rule 25 recognizes four situations, and the courts will not entertain substitution outside them. You cannot swap plaintiffs simply because someone better positioned has come along.
The first is death. If the underlying claim survives the plaintiff under the applicable state survivorship statute, the executor or personal representative of the estate can step in. Most personal injury, contract, and property claims survive; some claims tied purely to the individual, such as certain defamation or emotional distress claims, may not.
The second is incompetency. If the plaintiff can no longer make legal decisions, a guardian or conservator who has been appointed through a separate court proceeding can continue the case. The representative must already have legal authority to act before the court will approve substitution.
The third is transfer of interest. This comes up when a business plaintiff is acquired, merges, or sells the assets tied to the claim. The acquiring entity inherits the legal interest and can be substituted in. Under Rule 25(c), the original party can actually keep litigating after the transfer unless the court orders otherwise.
The fourth is a public officer leaving office. Here the successor is substituted automatically by operation of law. No motion is required, though a court can enter a formal order at any time.
The 90-Day Deadline After a Suggestion of Death
This is the timeline that ends cases. When a plaintiff dies, the 90-day clock does not start on the date of death. It starts when someone files and serves a “suggestion of death” on the court record. That is a separate, short document formally notifying the court and the parties that the plaintiff has died. Until it is properly served, the clock never runs.
Two consequences follow. If nobody files a suggestion of death, the case sits in limbo, and the successor or estate representative can take the time needed to organize and hire counsel. On the other hand, an opposing party who wants to force the issue can file the suggestion of death themselves and start the countdown.
Once served, the motion to substitute must be filed within 90 days. If it isn’t, the court must dismiss the deceased plaintiff’s claims. That dismissal is mandatory, not discretionary. There is one narrow escape: Rule 6(b) lets a court extend the period for good cause, but you have to ask, and courts are not generous with those requests after the deadline has already passed.
You do not have to wait for a suggestion of death before moving for substitution. The advisory committee notes to Rule 25 make clear that a party or the deceased’s representative can file the motion at any time after the death. Filing early is the safer approach.
For substitutions based on incompetency or transfer of interest, Rule 25 sets no specific deadline. But unreasonable delay that prejudices the other side can still sink the motion, and any scheduling order in the case may impose its own cutoff.
What to Put in the Motion
The motion has to give the court and the opposing parties enough to evaluate whether substitution is proper. Include:
- The case caption, matching the format used throughout the case
- The full legal name and address of the proposed substitute plaintiff
- The relationship between the new party and the original plaintiff, whether estate representative, successor in interest, or legal guardian
- The specific legal basis for substitution and why the proposed replacement qualifies as a proper party
- For death cases, an explanation of why the claim survives under the applicable state survivorship law. Courts take this seriously; not every claim survives.
Supporting Documents
What you attach depends on why you’re substituting.
For a deceased plaintiff, include a certified death certificate along with documentation of the new party’s authority to act for the estate. Letters of administration or letters testamentary from a probate court are the standard proof, and some courts specifically require certified or sealed copies.
For incompetency, attach the court order appointing the guardian or conservator.
For a business transfer of interest, attach whatever documents show the transfer occurred: articles of merger, an acquisition agreement, or an assignment of rights.
Proposed Order
Many courts want a proposed order filed alongside the motion. It’s a short separate document containing the ruling you want the judge to sign, typically granting the motion and naming the new party. Check the local rules before filing. Some jurisdictions will reject a motion that arrives without one.
Serving the Motion
Filing goes through the clerk, usually electronically. Service is where people slip up.
Serving the existing parties is straightforward. You deliver the motion and attachments to their attorneys the same way you serve any other document in the case, usually by electronic service or mail.
The non-party piece is different. If the proposed substitute plaintiff has not yet appeared in the case, they must be served using formal service of process, the same way you would serve an original complaint. That typically means personal delivery by a process server or sheriff, not a mailed copy. This trips people up because most mid-case motions only need to reach the existing parties’ attorneys. The court will not grant substitution if the proposed new plaintiff was never properly notified.
What Happens After Filing
Once served, the opposing parties have a window to object in writing. Typical objections argue that the proposed substitute is not a proper party, that the underlying claim did not survive the plaintiff’s death, or that the motion was filed too late.
Courts grant timely substitution motions in the large majority of cases. Rule 25 uses permissive language (“the court may order substitution”), so judges have some discretion, but denial is unusual when the motion arrives within the 90 days and the paperwork is in order. Courts push back mainly on long, unexplained delays, especially where circumstances have shifted enough to make substitution unfair to the other side.
If the motion is granted, the court issues an order amending the caption to reflect the new plaintiff, and the case continues. If it’s denied, the lawsuit either proceeds with the original plaintiff (if that person can still litigate) or faces dismissal.