The Colorado motion to dismiss: six grounds, and it must be filed by the answer date
Colorado procedure · Last verified August 17, 2026
Colorado's Rule 12 looks familiar to anyone who has read the federal rule, with one important difference in the timing clause: the motion must be filed on or before the date the answer is due.
There is no separate motion deadline to discover. It is the answer date.
Twenty-one days, or thirty-five
C.R.C.P. 12(a)(1):
A defendant shall file his answer or other response within 21 days after the service of the summons and complaint, except as otherwise provided by rule or statute. The filing of a motion permitted under this Rule alters these periods of time, as follows:
(A) if the court denies the motion or postpones its disposition until the trial on the merits, the responsive pleadings shall be filed within 14 days after notice of the court's action;
(B) if the court grants a motion for a more definite statement, or for a statement in separate counts or defenses, the responsive pleadings shall be filed within 14 days after the service of the more definite statement or amended pleading.
And 12(a)(2) extends it in three situations:
If, pursuant to special order, a copy of the complaint is not served with the summons, or if the summons is served outside of Colorado or by publication, the time limit for filings under subsections (a)(1) and (e) of this Rule shall be within 35 days after the service thereof.
| Situation | Time to answer or move |
|---|---|
| Ordinary service in Colorado | 21 days |
| Served outside Colorado, or by publication, or where the complaint was not served with the summons | 35 days |
| After a denied motion | 14 days from notice |
| After a granted more-definite-statement motion | 14 days from service of it |
Note that a denial gives you 14 days, not a fresh 21.
The six grounds — and the filing deadline inside the sentence
C.R.C.P. 12(b):
How Presented. Every defense, in law or in fact, to a claim for relief in any pleading, whether a claim, counterclaim, cross-claim, or third-party claim, shall be asserted in the responsive pleading thereto if one is required, except that the following defenses may at the option of the pleader be made by separate motion filed on or before the date the answer or reply to a pleading under C.R.C.P. 12(a) is due:
(1) lack of jurisdiction over the subject matter; (2) lack of jurisdiction over the person; (3) insufficiency of process; (4) insufficiency of service of process; (5) failure to state a claim upon which relief can be granted; or (6) failure to join a party under C.R.C.P. 19.
The deadline is embedded in the introductory clause: "by separate motion filed on or before the date the answer … is due." Diary the answer date, and treat it as the motion date too.
Colorado's list is six, not seven — there is no improper-venue ground here. Venue is handled under C.R.C.P. 98, and the rule acknowledges that: no defence is waived "by being joined with one or more other defenses or objections in a responsive pleading or with any other motion permitted under this Rule or C.R.C.P. 98."
Combining is safe
The same subsection confirms it:
No defense or objection is waived by being joined with one or more other defenses or objections in a responsive pleading or with any other motion permitted under this Rule or C.R.C.P. 98.
So there is no tactical reason to file them separately — and good reason not to, given the waiver rule below.
Three grounds you can waive
C.R.C.P. 12(h)(1):
A defense of lack of jurisdiction over the person, insufficiency of process, or insufficiency of service of process is waived:
(A) If omitted from a motion in the circumstances described in section (g); or (B) if it is neither made by motion under this Rule nor included in a responsive pleading or an amendment thereof permitted by Rule 15(a) to be made as a matter of course.
Three defences are at risk — personal jurisdiction, insufficiency of process, insufficiency of service. File a Rule 12 motion and leave one of them out, and it is gone.
Subject matter jurisdiction and failure to state a claim are not on that list and are preserved longer.
Conversion
The end of 12(b):
If, on a motion asserting the defense numbered (5) to dismiss for failure of the pleading to state a claim upon which relief can be granted, matters outside the pleading are presented to and not excluded by the court, the motion shall be treated as one for summary judgment and disposed of as provided in C.R.C.P. 56, and all parties shall be given reasonable opportunity to present all material made pertinent to such a motion by C.R.C.P. 56.
Only ground (5) converts. And 12(c) applies the same conversion rule to a motion for judgment on the pleadings, available "After the pleadings are closed but within such time as not to delay the trial."
If conversion happens, see responding to summary judgment in Colorado.
You can insist on an early ruling
C.R.C.P. 12(d) is worth knowing and rarely invoked:
Preliminary Hearings. The defenses specifically enumerated in subsections (1)-(6) of section (b) of this Rule, whether made in a pleading or by motion, and the motion for judgment mentioned in section (c) of this Rule, shall be heard and determined before trial on application of any party, unless the court orders that the hearing and determination thereof be deferred until the trial.
"Shall be heard and determined before trial on application of any party." A defence raised in the answer rather than by motion can still be brought on for decision early.
The rest of the case
Two Colorado features to plan around once the motion is resolved:
Disclosures come fast. C.R.C.P. 26(a)(1) requires disclosure within 28 days after the case is at issue, and the excuses are foreclosed — see Colorado's mandatory disclosures.
Commencement may have been by service. Colorado allows an action to be commenced by service, with the complaint filed within 14 days — and the requirement is waived by answering without reserving it. See starting a Colorado civil case.
That second point belongs on the same checklist as the Rule 12 defences: if the complaint was filed late after service, reserve the issue in the first responsive pleading or motion.
How Colorado compares
| Colorado | Wisconsin | Minnesota | Federal | |
|---|---|---|---|---|
| Time to answer | 21 days | 20 days (45 in tort) | 21 days | 21 days |
| Longer period for out-of-state service | 35 days | — | — | — |
| Enumerated grounds | six | ten | — | seven |
| Venue in the same rule | no — C.R.C.P. 98 | no — s. 801.51 | yes | yes |
| Motion deadline | the answer date | before pleading | before pleading | the answer date |
| Time after a denial | 14 days | 10 days | 10 days | 14 days |
| Automatic discovery stay | no | yes, 180 days | no | no |
| Right to a pre-trial ruling | yes, on application | — | — | discretionary |
A short checklist
- Diarise 21 days — or 35 if service was outside Colorado, by publication, or without the complaint.
- File the motion on or before the answer date. That is the deadline, stated inside Rule 12(b).
- Put every ground in the one motion. Combining waives nothing, and omitting can.
- Watch the three waivable defences — personal jurisdiction, process, service.
- Raise venue under C.R.C.P. 98, alongside, not inside, the Rule 12 motion.
- Check whether the case was commenced by service and the complaint filed within 14 days; reserve the issue if not.
- Expect only ground (5) to convert to summary judgment on outside material.
- Ask for a preliminary determination under 12(d) if you want the defence decided before trial.
- Diarise the disclosure deadline — 28 days after the case is at issue, whatever happens to the motion.
Where these rules live
- C.R.C.P. 12 — Defenses and Objections
- C.R.C.P. 15 — Amended and Supplemental Pleadings
- C.R.C.P. 19 — Joinder of Persons Needed for Just Adjudication
- C.R.C.P. 26 — General Provisions Governing Discovery
- C.R.C.P. 56 — Summary Judgment
- C.R.C.P. 98 — Place of Trial
This page explains what the rules say. It isn't legal advice, and the standard for dismissal under C.R.C.P. 12(b)(5) is developed in case law this site doesn't cover.