The plaintiff may amend any defect, mistake or informality in the writ, complaint or petition and insert new counts in the complaint, which might have been originally inserted therein, without costs, during the first thirty days after the return day. (See General Statutes § 52-128 and annotations.) Any writ, complaint or petition amended pursuant to this section shall be accompanied by a separate document showing the portion or portions of the original writ, complaint or petition so amended by using underlining to indicate new language and by using either brackets or strikethrough to indicate deleted language.
Section 10-59.Amendments; Amendment as of Right by Plaintiff
Current through August 12, 2025 (2026 Practice Book edition) · Last verified July 9, 2026
In one sentenceA Connecticut plaintiff may amend defects, mistakes, or informalities in the writ, complaint, or petition, and add new counts, without cost or court permission, during the first thirty days after the return day.
Full Text of Section 10-59
Amendment History
(P.B. 1978-1997, Sec. 175.) (Amended June 11, 2021, to take effect Jan. 1, 2022.)
Plain-English Summary
Section 10-59 gives the plaintiff a window to fix problems in the writ, complaint, or petition on their own, without asking the court and without paying costs. That window runs for the first thirty days after the return day, and during it the plaintiff may correct any defect, mistake, or informality, and may insert new counts that could have been included in the original pleading.
Any amendment made under this section must come with a separate document showing exactly what changed — new language underlined, and deleted language shown in brackets or with strikethrough — so the court and other parties can see the amendment against the original pleading at a glance.
Frequently Asked Questions
How long does a Connecticut plaintiff have to amend as of right?
The plaintiff may amend defects, mistakes, or informalities, and add new counts, during the first thirty days after the return day, without cost.
Does the plaintiff need the court’s permission to amend within thirty days of the return day?
No. Within that thirty-day window, Section 10-59 lets the plaintiff amend without seeking leave of the judicial authority.
What must accompany an amendment made under Section 10-59?
A separate document showing the changes, with underlining for new language and brackets or strikethrough for deleted language.
Can a plaintiff add an entirely new claim under this section?
Only new counts that could have been originally inserted in the complaint; the section does not address claims outside that scope.
Source & verification. The section text is reproduced verbatim from the
official Connecticut Practice Book (Conn. Practice Book § 10-59). Prescribed by the Judges of the Superior Court of Connecticut (Conn. Gen. Stat. Section 51-14). The plain-English summary is original and written by us. Last verified July 9, 2026. ·
Official source
Also known as: amendment as of right Connecticutamend complaint within thirty days of return dayadding new counts to a complaint CTplaintiff amendment without leave of court