Starting a Colorado civil case: two ways to commence, and a 14-day trap in one of them
Colorado procedure · Last verified August 17, 2026
Colorado is one of the few states that lets you start a lawsuit either by filing or by serving. That flexibility is useful when a limitations period is about to run.
It also comes with a 14-day fuse, and the rule says an untimely filing makes the service "ineffective and void without notice."
Two ways to commence
C.R.C.P. 3(a):
How Commenced. A civil action is commenced (1) by filing a complaint with the court, or (2) by service of a summons and complaint. If the action is commenced by the service of a summons and complaint, the complaint must be filed within 14 days after service. If the complaint is not filed within 14 days, the service of summons shall be deemed to be ineffective and void without notice. In such case the court may, in its discretion, tax a reasonable sum in favor of the defendant to compensate the defendant for expense and inconvenience, including attorney's fees, to be paid by the plaintiff or his attorney. The 14 day filing requirement may be expressly waived by a defendant and shall be deemed waived upon the filing of a responsive pleading or motion to the complaint without reserving the issue.
Four things in that paragraph.
Either route commences the action. Filing works. So does service, with nothing on file.
Service-first has a 14-day filing deadline, and the consequence is severe: the service becomes "ineffective and void without notice." No motion by the defendant, no order — it simply fails.
Costs can follow. The court may tax a reasonable sum against the plaintiff or the plaintiff's attorney for the defendant's expense and inconvenience, including attorney's fees.
But it is waivable — and easily waived by the defendant. The requirement "shall be deemed waived upon the filing of a responsive pleading or motion to the complaint without reserving the issue."
That last sentence cuts both ways. A defendant who wants to rely on the missed 14 days must reserve the issue in the first responsive pleading or motion. Answering without reserving it hands the plaintiff the point.
When jurisdiction attaches
C.R.C.P. 3(b):
Time of Jurisdiction. The court shall have jurisdiction from (1) the filing of the complaint, or (2) the service of the summons and complaint; provided, however, if more than 14 days elapses after service upon any defendant before the filing of the complaint, jurisdiction as to that defendant shall not attach by virtue of the service.
Note "as to that defendant." The 14 days runs defendant by defendant, so in a multi-defendant case served on different dates, jurisdiction can attach as to some and fail as to others.
| Route | Commencement | Condition |
|---|---|---|
| File the complaint | on filing | none |
| Serve the summons and complaint | on service | complaint filed within 14 days, per defendant |
Which route to use
Service-first commencement exists for a reason: it stops a limitations period on the day of service, without waiting for a filing to be accepted. Where a deadline is hours away and service can be effected, it is the tool.
For everything else, filing first is simpler and carries no 14-day exposure.
What goes in the complaint
Colorado pleads under C.R.C.P. 8(a), which requires a short and plain statement of the claim and a demand for judgment, and C.R.C.P. 10 governs the form — caption, numbered paragraphs, and separate counts. C.R.C.P. 11 carries the signature and certification requirements.
Two practical points that follow from rules covered elsewhere on this site:
- Rule 54(c) limits a default judgment to the relief demanded, so the demand for judgment in the complaint sets the ceiling if the defendant never appears. That matters more than it looks — see setting aside a Colorado default judgment.
- Rule 26(a)(1) disclosures are due 28 days after the case is at issue, which arrives sooner than most people expect — see Colorado's mandatory disclosures.
Service
C.R.C.P. 4 governs process. The essential sequencing point for this guide is that a summons served before any complaint is filed is only good if the complaint follows inside 14 days — so if you commence by service, the filing should already be prepared.
How Colorado compares
| Colorado | Minnesota | Wisconsin | Federal | |
|---|---|---|---|---|
| Commence by filing | yes | no | yes | yes |
| Commence by service | yes | yes, the only way | no | no |
| Deadline after service-first | 14 days to file | 1 year to file | — | — |
| Consequence of missing it | service void without notice | dismissed with prejudice | — | — |
| Waivable by the defendant | yes, and waived by answering without reserving | — | — | — |
| Fee exposure for the lapse | yes, against party or attorney | — | — | — |
Colorado, Minnesota and Wisconsin between them cover every combination — and the penalties are very different, so a practitioner moving between them should not assume anything.
A short checklist
- Decide which route you are using before you serve anything.
- If you commence by service, diarise 14 days to file — separately for each defendant.
- Have the complaint ready to file before serving it. The 14 days is not long, and the consequence is void service.
- If you are the defendant and the complaint was filed late, reserve the issue in your first responsive pleading or motion. Answering without reserving waives it.
- Consider asking for costs if you are the defendant put to expense by a void service — the rule allows them against the plaintiff or the attorney.
- Check jurisdiction defendant by defendant where service dates differ.
- Set the demand for judgment carefully — Rule 54(c) caps a default judgment at what was demanded.
- Diarise the disclosure deadline — 28 days after the case is at issue under Rule 26(a)(1).
Where these rules live
- C.R.C.P. 3 — Commencement of Action
- C.R.C.P. 4 — Process
- C.R.C.P. 8 — General Rules of Pleading
- C.R.C.P. 10 — Form of Pleadings
- C.R.C.P. 11 — Signing of Pleadings
- C.R.C.P. 12 — Defenses and Objections
- C.R.C.P. 54 — Judgments; Costs
This page explains what the rules say. It isn't legal advice, and the limitations periods that make the commencement date matter are set by statute rather than by the rules reproduced here.