Free Colorado 21-Day Notice to Terminate Month-to-Month Tenancy
Colorado 21-day notice to terminate a month-to-month tenancy under C.R.S. § 13-40-107(2)(c). Applies to tenancies that have lasted 1 month or longer but less than 6 months.
The Colorado 21-day notice to terminate is the statutory written notice required by C.R.S. § 13-40-107(2)(c) for ending a month-to-month tenancy that has lasted 1+ month but less than 6 months. Longer tenancies require longer notice: 28 days for 6+ months but less than 1 year; 91 days for tenancies of 1 year or longer. The notice must be in writing, describe the property, and state the specific date the tenancy will terminate.
Colorado MTM Termination at a Glance
Statute
C.R.S. § 13-40-107
Notice Period
21 Days
Tenancy Length
1–6 months
After Notice
FED if no vacancy
⚠ Colorado Statutory Requirement
C.R.S. § 13-40-107(2)(c) requires at least 21 days’ written notice for a month-to-month tenancy of 1–6 months. For tenancies of 6+ months but less than 1 year, the period is 28 days. For tenancies of 1+ year, the period is 91 days. The notice must describe the property and state the specific termination date.
How to Serve the Colorado MTM Termination
Determine the correct notice period
Confirm tenancy length. C.R.S. § 13-40-107 requires 21 days for 1–6 month tenancies, 28 days for 6–12 months, and 91 days for 1+ year. Using the wrong period invalidates the notice.
Prepare the notice
Prepare the written notice under C.R.S. § 13-40-107. The notice must describe the property and the specific date the tenancy terminates. It must be signed by the landlord or authorized agent.
Serve the notice
Serve per C.R.S. § 13-40-108: personal service, substituted service (left with a family member over fifteen residing on or in charge of the premises), or posting, which is permitted only after attempts at personal service on at least two separate days. Retain proof of service.
Wait the statutory period
Wait the full 21-day notice period before any further action. The termination is effective on the date stated in the notice.
Document and follow up
If the tenant has not vacated by the termination date, file a forcible entry and detainer (FED) action in Colorado county court. Just-cause protections under HB24-1098 may apply to longer tenancies.
Generate the Colorado Notice
Complete the fields below to generate a Colorado 21-day month-to-month termination notice. State the lease/tenancy details and the termination date. Service must comply with C.R.S. § 13-40-108; retain proof of service.
ℹ Colorado 21-day notice (C.R.S. § 13-40-107)
Use 21 days for tenancies of 1+ month but less than 6 months. For longer tenancies: 28 days (6 mo.–12 mo.) or 91 days (1+ year). The notice must state the specific termination date, not just "21 days from service."
1. Notice Header (From / To / Property)
From (Landlord / Property Manager)
To (Tenant)
2. Tenancy / Lease Information
3. Notice Content
4. Signature
About This Colorado Notice
The Colorado 21-day notice to terminate a month-to-month tenancy is the statutory notice required by C.R.S. § 13-40-107(2)(c) for ending tenancies that have lasted 1+ month but less than 6 months. Colorado scales the notice period with tenancy length: 21 days (1–6 months), 28 days (6 months to under a year), and 91 days (1 year or longer). The notice must be in writing, describe the property, state the specific date the tenancy will terminate, and be signed by the landlord or authorized agent. Service must comply with C.R.S. § 13-40-108: personal service, substituted service, or posting, which is permitted only after attempts at personal service on at least two separate days. Critical Colorado considerations: (1) using the wrong notice period invalidates the notice; (2) the notice must state a specific termination date, not "21 days from service"; (3) HB24-1098 introduced just-cause eviction protections for tenancies of 12+ months in many cases, which may affect whether no-cause termination is permitted. Best practice: confirm tenancy length, use the correct notice period, state a specific calendar termination date, include a property description, sign the notice, cite C.R.S. § 13-40-107, serve per C.R.S. § 13-40-108, and retain proof of service. Consult Colorado counsel for longer tenancies that may be subject to just-cause protections.
Colorado Statutory Requirements
- Statute: C.R.S. § 13-40-107 (Notice to Terminate Tenancy)
- Notice period: 21 days (tenancy 1–6 months); 28 days (6–12 months); 91 days (1+ year)
- Must be in writing
- Must describe the property
- Must state the specific termination date
- Must be signed by the landlord, tenant, or authorized agent
- Service per C.R.S. § 13-40-108
Service Methods Permitted
- Personal service on the tenant (C.R.S. § 13-40-108)
- Substituted service — leave with a family member over fifteen residing on or in charge of the premises
- Posting on the premises, only after attempts at personal service on at least two separate days
- Certified mail — supplemental; verify with local court
- Retain affidavit of service — required for FED case
Common Mistakes
- Wrong notice period — using 21 days for a 1+ year tenancy (should be 91)
- Vague termination date — must state specific date, not "21 days from service"
- No property description — required by C.R.S. § 13-40-107(3)(a)
- Missing signature — required by C.R.S. § 13-40-107(3)(b)
- Improper service — not meeting C.R.S. § 13-40-108
- Ignoring just-cause requirements for longer tenancies (HB24-1098)
Best Practices
- Confirm tenancy length first — use the right period
- State a specific calendar date for termination
- Include property description — address with unit number, city, county
- Sign the notice — landlord or authorized agent
- Cite C.R.S. § 13-40-107 on the notice
- Personal service preferred — retain affidavit
- Consider just-cause rules for tenancies of 12+ months
Bottom line
Colorado requires a 21-day notice for MTM tenancies of 1–6 months under C.R.S. § 13-40-107(2)(c). Use 28 days (6–12 mo.) or 91 days (1+ year) for longer tenancies. State a specific calendar date, include a property description, sign the notice, serve per C.R.S. § 13-40-108, and retain proof.
Which Colorado statute sets the 21-day period, and which bill actually created it?
Colorado’s month-to-month termination notice periods live in C.R.S. § 13-40-107, and the 21-day figure was set by Senate Bill 17-245, effective August 9, 2017. If you have seen the 21 days attributed to House Bill 23-1095, that is wrong: HB 23-1095 is “Prohibited Provisions In Rental Agreements,” effective August 7, 2023, and governs clauses a written lease may not contain — jury-trial waivers, one-way fee-shifting, fees recharacterized as “rent.” It does not touch notice periods.
SB 17-245 was captioned “Concerning a twenty-one-day notice requirement in tenancies of one month or more but less than six months,” and it raised that tier from seven days to twenty-one. The section was reshaped most recently by House Bill 24-1098, effective April 19, 2024, which renamed § 13-40-107 from “Notice to quit” to “Notice to terminate tenancy,” moved the tier list from subsection (1) into subsection (2), and repealed the old subsection (3) tenancy-at-will presumption and the old subsection (5) condominium carve-out. A Colorado notice built from a pre-2024 template will cite the wrong subsections.
The complete Colorado tier table under C.R.S. § 13-40-107(2)
Each tier is stated as an “at least” minimum, and the notice must be served before the end of the period or fixed term.
| Length of the tenancy | Minimum written notice | Colorado citation |
|---|---|---|
| One year or longer | At least 91 days | C.R.S. § 13-40-107(2)(a) |
| Six months or longer but less than a year | At least 28 days | C.R.S. § 13-40-107(2)(b) |
| One month or longer but less than six months | At least 21 days | C.R.S. § 13-40-107(2)(c) |
| One week or longer but less than one month, or a tenancy at will | At least 3 days | C.R.S. § 13-40-107(2)(d) |
| Less than one week | At least 1 day | C.R.S. § 13-40-107(2)(e) |
The tier is set by how long the tenancy has run, not by how rent is billed. A Colorado tenant who has paid month to month for fourteen months sits in the 91-day tier, not the 21-day tier, even though the rental period is one month.
Can a Colorado landlord still send a bare 21-day no-cause notice after HB 24-1098?
Often, no. HB 24-1098 added Part 13 to article 12 of title 38, “For Cause Eviction Policy,” at C.R.S. §§ 38-12-1301 through 38-12-1303. Under C.R.S. § 38-12-1303(1), a landlord “shall not serve a notice to terminate tenancy or a demand for possession or otherwise proceed with an action for unlawful detainer” under article 40 of title 13 unless there is cause. The restriction was written into the notice statute too: C.R.S. § 13-40-107(1) now says only a landlord of nonresidential real property, or of a residential premises described in C.R.S. § 38-12-1302(1)(a), (1)(b), (1)(d), (1)(e), or (1)(f), may terminate a periodic tenancy this way. Any tenant may still use it; a Colorado landlord outside those exempt categories cannot.
Who is outside the for-cause rule
C.R.S. § 38-12-1302(1) applies Part 13 to every residential premises in Colorado except:
- A short-term rental property — under § 38-12-1301(12), leased for fewer than thirty consecutive days for temporary, recreational, business or transient purposes, or leased for less than six months by a tenant back from the landlord to whom that tenant sold the premises.
- Owner-occupied small property — a single-family home with or without an accessory dwelling unit, a duplex, or a triplex, where the owner or master tenant lives in it, or on an adjacent property, as a primary residence, and it is not a multifamily property of four or more dwelling units.
- A mobile home space leased to a home owner, or under a lease-to-own or purchase-option agreement.
- A residential premises leased under an employer-provided housing agreement, defined at C.R.S. § 13-40-104(5)(a) as a residential tenancy agreement between an employee and an employer where the employer or an affiliate acts as landlord.
- A residential tenant who has not been a tenant of the premises for at least twelve months.
- A residential tenant not known to the landlord to be a tenant of the premises.
The twelve-month exemption matters most here. The 21-day tier serves tenancies of one to six months, which are by definition under twelve months, so Part 13 does not apply and a plain 21-day notice remains available. Section 13-40-107(1) reaches that result by cross-referencing § 38-12-1302(1)(e), so the two provisions agree.
The no-fault grounds, and why they run 90 days
Where Part 13 applies, C.R.S. § 38-12-1303(3) lists the only “no-fault eviction” grounds: demolition or conversion; substantial repairs or renovations; occupancy by the landlord or a landlord’s family member; withdrawal from the rental market to sell a single-family home, townhome, duplex, triplex or individual condominium unit; a tenant’s refusal to sign a new rental agreement with reasonable terms; and a history of nonpayment of rent. Each requires at least ninety days’ written notice, properly served, during which the tenant may remain on the existing agreement’s terms; the sole exception is a landlord on active military duty, or that landlord’s spouse, taking occupancy, which C.R.S. § 38-12-1303(3)(c)(II) sets at forty-five days. Under C.R.S. § 38-12-1303(5)(b), the notice must state the legal and factual basis for the no-fault eviction, and that legal basis must be one set out in subsection (3).
Does the same 21-day period apply to a Colorado rent increase?
No — a Colorado residential rent increase carries its own, longer notice. Under C.R.S. § 38-12-701(2)(a), in a residential tenancy with no written agreement between landlord and tenant, a landlord may increase rent only on at least sixty days’ written notice. The 21-day figure in that section, at C.R.S. § 38-12-701(1), applies to a nonresidential tenancy of one month or longer but less than six months with no written agreement. Do not carry the 21 days across.
Two further limits apply. C.R.S. § 38-12-702(1) bars a landlord from increasing residential rent more than once in any twelve-month period of consecutive occupancy, regardless of a written agreement, the length of the tenancy, or whether it is fixed, month-to-month or of indefinite term. And C.R.S. § 38-12-701(2)(b), as amended by HB 24-1098, provides that a landlord shall not terminate a residential tenancy with no written agreement by serving a notice to terminate tenancy with the primary purpose of raising rent inconsistently with that section — which is exactly a 21-day termination used to sidestep the 60-day increase rule.
How are Colorado mobile home park tenancies different?
They run under a separate statute and the 21-day notice does not apply. Mobile home park tenancies fall under the Mobile Home Park Act, part 2 of article 12 of title 38. C.R.S. § 38-12-202(1)(a) requires a written lease and a served notice to terminate tenancy before any park tenancy ends, and § 38-12-202(1)(c)(I) gives the home owner at least ninety days after service or posting to sell the home or remove it — cut to at least ten days where the ground is the conduct described in § 38-12-203(1)(f). C.R.S. § 38-12-203(1) sets a closed list of permitted reasons for termination, so Colorado parks have had a cause requirement independent of HB 24-1098.
Two Colorado sections are easy to confuse here. C.R.S. § 38-12-204.3, “Notice required for termination,” is a mobile home park provision prescribing the plain-language notice, in at least ten-point type, that must accompany a park notice to terminate tenancy or notice of nonpayment of rent. It is not a rent-increase statute. The park rent-increase rule is C.R.S. § 38-12-204(2), requiring sixty days’ written notice plus management ownership information, with C.R.S. § 38-12-204(3) limiting park increases to once in any twelve-month period. General residential increases run under C.R.S. §§ 38-12-701 and 38-12-702 instead.
When does the clock start, and what does the notice actually accomplish?
The Colorado notice must expire at the end of the rental period, not merely twenty-one days after you hand it over. C.R.S. § 13-40-107(1) permits termination of a periodic tenancy “at the end of the tenancy period” by serving written notice “that expires at the end of the period,” and § 13-40-107(2) requires service before the end of that period. For a Colorado month-to-month tenancy running the first through the last day of the month, a 21-day notice served on the 5th cannot terminate on the 26th; it must name the last day of a rental period at least twenty-one days out. C.R.S. § 13-40-107(3) requires the notice to describe the property, state the particular date the tenancy will terminate, and carry the signature of the party giving it or that party’s agent or attorney.
Service is governed by C.R.S. § 13-40-108, which HB 24-1098 retitled “Service of notice to vacate or demand” and tightened. Personal delivery to a known tenant or other occupant is the primary method; the notice may instead be left with a member of the tenant’s family over the age of fifteen residing on the premises, or with a person in charge of the premises. Posting is now a fallback that unlocks only after attempts at personal service at least once on two separate days — a Colorado landlord who posts after one visit has not served properly. Keep dated records of both attempts; proof of service is what carries the later filing.
The expired notice is a precondition, not an eviction. Nothing in C.R.S. § 13-40-107 gives a Colorado landlord possession or authorizes a lockout. Once the stated date passes and the tenant remains, the holdover becomes an unlawful detention under C.R.S. § 13-40-104(1)(c) — or § 13-40-104(1)(e.8) where the landlord properly initiated a no-fault eviction under § 38-12-1303(3) — and the route to possession is a forcible entry and detainer action in county court. Accepting rent for a period beginning after the termination date works against the notice: § 13-40-107(1) authorizes a notice that expires at the end of the rental period, and taking rent for a further period restarts a period the notice was never drafted to end. Do not take the next month’s rent while you decide; serve a fresh notice on the correct tier.
Frequently Asked Questions
What is a Colorado 21-day notice to terminate?
A Colorado 21-day notice to terminate is the statutory notice required by C.R.S. § 13-40-107(2)(c) for ending a month-to-month tenancy that has lasted 1+ month but less than 6 months. The notice must be in writing, describe the property, state the specific termination date, and be signed.
When do I use 28 days or 91 days instead?
Colorado scales the notice period with tenancy length under C.R.S. § 13-40-107: 21 days for 1–6 month tenancies, 28 days for 6 months to under a year, and 91 days for tenancies of 1 year or longer. Using the wrong period invalidates the notice.
How must the Colorado notice be served?
Service must comply with C.R.S. § 13-40-108: personal service on the tenant, substituted service (left with a family member over fifteen residing on or in charge of the premises), or posting, which is permitted only after attempts at personal service on at least two separate days. Retain an affidavit of service — without proof of service, the FED case may be dismissed.
What happens if the tenant doesn’t vacate?
If the tenant has not vacated by the termination date, the landlord may file a forcible entry and detainer (FED) action in Colorado county court. The court can issue a judgment for possession; the sheriff then executes the lockout.
Do just-cause protections apply?
Colorado HB24-1098 introduced just-cause eviction protections for certain tenancies. The protections most clearly apply to tenancies of 12+ months, which makes the 91-day notice category most affected. For a 21-day MTM (1–6 month tenancy), no-cause termination is generally still permitted, but consult Colorado counsel for any tenancy that has lasted close to or beyond 12 months.
Can the tenant cure or stop the termination?
Colorado generally does not provide a statutory cure right for no-fault termination of a month-to-month tenancy. The tenant may negotiate with the landlord for a new tenancy, but the landlord is not obligated to renew.
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