Amending a New York pleading: three windows under CPLR 3025(a), and what leave requires

New York procedure · Last verified August 17, 2026

CPLR 3025 is short and unusually generous. The part people misread is subdivision (a), which is not one deadline but three alternatives, any of which will do.

One amendment, three ways in — CPLR 3025(a)

A party may amend his pleading once without leave of court:
- within twenty days after its service, or - at any time before the period for responding to it expires, or - within twenty days after service of a pleading responding to it.

Any one of the three suffices. That matters most for a plaintiff: the third window reopens the right after the defendant answers. A complaint served in January and answered in March can still be amended as of right within twenty days of that answer, even though the first two windows closed long ago.

The right is once. Using one window uses it up.

After that — leave, freely given, with one formality

CPLR 3025(b):

A party may amend his or her pleading, or supplement it by setting forth additional or subsequent transactions or occurrences, at any time by leave of court or by stipulation of all parties. Leave shall be freely given upon such terms as may be just including the granting of costs and continuances. Any motion to amend or supplement pleadings shall be accompanied by the proposed amended or supplemental pleading clearly showing the changes or additions to be made to the pleading.

Three things.

No outer deadline in the rule. "[A]t any time." New York has no scheduling-order cutoff of the sort FRCP 16(b)(4) imposes, so the practical limits are prejudice and the court's discretion rather than a date.

Amendment and supplementation are the same motion. Unlike FRCP 15(d) and O.C.G.A. § 9-11-15(d), which treat supplemental pleadings separately, CPLR 3025(b) folds them together — a supplemental pleading sets out "additional or subsequent transactions or occurrences."

The markup is mandatory. The motion "shall be accompanied by the proposed amended or supplemental pleading clearly showing the changes or additions." A clean copy is not what the rule asks for; a redlined or otherwise marked version is. Motions get denied on this.

Stipulation is the other route, and it needs all parties.

Conforming to the evidence — CPLR 3025(c)

The court may permit pleadings to be amended before or after judgment to conform them to the evidence, upon such terms as may be just including the granting of costs and continuances.

Before or after judgment. That is broader than it looks, and it is the provision that rescues a case tried on a theory the pleadings didn't quite capture.

Responding to an amended pleading — CPLR 3025(d)

Except where otherwise prescribed by law or order of the court, there shall be an answer or reply to an amended or supplemental pleading if an answer or reply is required to the pleading being amended or supplemented. Service of such an answer or reply shall be made within twenty days after service of the amended or supplemental pleading.

Twenty days, and only if the original required a response. An amendment to a pleading that needed no answer doesn't create one.

Where the limitations question lives

Relation back in New York is governed by CPLR 203, not by CPLR 3025. CPLR 203(f) provides that a claim asserted in an amended pleading is deemed interposed at the time the claims in the original pleading were interposed, unless the original pleading did not give notice of the transactions or occurrences to be proved.

For adding a party, the doctrine is more demanding, and the governing test comes from New York case law rather than from the text of CPLR 203 — which is where our coverage stops.

How this fits with a motion to dismiss

CPLR 3211(e) contains its own amendment provision at the end: on a motion to dismiss made under subdivision (a) or (b), the court may permit the responding party to plead over where the motion is based on a ground that could be cured by amendment.

And because CPLR 3025(a)'s second window runs "at any time before the period for responding to it expires," a plaintiff facing a CPLR 3211 motion may still be inside that window — the motion doesn't itself close it. Worth checking before opposing.

Compared with the systems we cover

	New York CPLR 3025	Federal Rule 15	California CCP 472	Georgia § 9-11-15
Amendments as of right	one, via any of three windows	one	one	unlimited
Reopens after the other side pleads	yes — 20 days after a responsive pleading	no	no	n/a
Later cutoff	none in the rule	Rule 16(b)(4) scheduling order	none — CCP 576	entry of the pretrial order
Markup required with the motion	yes	no	no	no
Supplemental pleadings	same subdivision as amendments	separate, Rule 15(d), motion required	—	separate, § 9-11-15(d)
Response to an amendment	20 days	14 days or the time remaining, whichever is later	30 days (CCP 471.5)	15 days, when ordered

The short version

Check all three windows in CPLR 3025(a) before assuming you need leave — the third one reopens after a responsive pleading.
If you need leave, attach the marked-up pleading. The rule requires it in terms.
Or get a stipulation — CPLR 3025(b) treats it as equivalent, and it needs no motion.
Calendar 20 days for the other side's response under CPLR 3025(d).
If limitations are in play, the analysis is CPLR 203, not CPLR 3025.

Where these rules live

The New York courts publish self-help material at nycourts.gov. This page explains what the CPLR says. It isn't legal advice.

How this guide is sourced. Every procedural statement here is drawn from the text of the rules named above, each of which is reproduced verbatim on its own page on this site. Quoted rule language appears in quotation marks or block quotes; everything else is original writing. Last verified August 17, 2026.

This page explains what the rules say. It is legal information, not legal advice, and it cannot tell you how a rule applies to your situation. Deadlines are often short and some are not extendable — if the outcome matters, talk to a lawyer or your court’s self-help center.