What Colorado law actually requires
Colorado's residential security deposit rules live in three linked statutes: Colo. Rev. Stat. § 38-12-103, § 38-12-104, and § 38-12-105. Together they create a clear obligation, a firm deadline, and real financial consequences when the landlord misses it.
Under § 38-12-103, your landlord must return the deposit within one calendar month after the tenancy ends, provided you supply a forwarding address. Delivery can be in person or by first-class mail. Neither "I didn't have your address" nor "I'm still getting estimates" extends that window once you've given written notice of where to send it.
Section § 38-12-104 adds the itemization requirement. If the landlord withholds any portion of the deposit, they must send a written, itemized accounting of every deduction, delivered or mailed within the same one-month window. Vague line items like "cleaning and repairs" don't satisfy the statute. Each deduction needs a description and a dollar figure. If the landlord skips the accounting or sends it late, the deductions lose their legal footing.
What Colorado landlords can and cannot deduct
Colorado doesn't enumerate permitted deduction categories the way California does, but courts apply a consistent standard: deductions must reflect actual, documented losses the tenant caused, not routine maintenance or the normal aging of the property.
Deductions that hold up in Colorado courts include unpaid rent owed through the final day of tenancy, damage to the unit that goes beyond ordinary wear and tear (think large holes in drywall, broken fixtures, stained carpet from a spill, not faded paint or worn flooring from years of normal use), and cleaning costs when the unit was left materially dirtier than it was at move-in.
Deductions that don't hold up include repainting worn-but-intact walls, replacing carpet that was already near the end of its useful life, and speculative losses like "future repairs" without a completed invoice. If the landlord can't produce a receipt or a contractor's statement, the number won't survive scrutiny.
Colorado also has no statutory deposit cap. Unlike California, which limits deposits to two months' rent for unfurnished units, a Colorado landlord can collect any amount agreed to in the lease. That makes it worth double-checking your lease to confirm what you actually paid and whether any portion was labeled something other than "security deposit" (like a "pet deposit" or "damage deposit"). Those amounts are governed by the same statute.
The 30-day clock and why forwarding address matters
The one-month return window in Colorado is conditional in one important way: it starts when both things are true at once. You've vacated the property, and you've provided a forwarding address. If you moved out without giving the landlord a written address for the return, the clock hasn't started.
That said, this condition cuts both ways. If you gave a forwarding address at move-out or in writing any time after, the clock starts then. And if the landlord received the address from any written communication you sent (a text, an email, a certified letter) and still didn't return the deposit within 30 days of that, the statutory deadline applies.
Practically speaking: always give your forwarding address in writing. Put it in your move-out notice. Confirm it in a follow-up email the day you hand over the keys. This removes any ambiguity about when the 30-day window opened, and it closes off the most common argument landlords use to claim the clock never started.
Calculator
What you may be owed
Estimate only. Uses your state's return window and bad-faith multiplier. Not legal advice.
What you can recover under § 38-12-105
Colorado's penalty structure is different from states that use a simple multiplier. There's no "two times the deposit" formula here. What you can recover breaks down into three components.
First, the wrongfully withheld amount itself. Whatever portion of the deposit the landlord had no legal basis to keep, you're owed back in full.
Second, 12% annual interest on the wrongfully withheld amount, accruing from the date the landlord was required to return it. At 12% per year, interest on a $1,500 withheld deposit accrues at about $180 per year, which is not trivial for a landlord who drags things out.
Third, reasonable attorney's fees. This is the provision that gives a demand letter its real leverage. Even if you don't hire an attorney, the statutory right to fees means that if you escalate to small claims and win, the court can award costs. More importantly, a landlord's attorney will flag the fees exposure immediately, which often prompts payment before court.
The total recovery ceiling for most disputes is the withheld amount plus accumulated interest plus any documented costs. Colorado's small claims limit is $7,500, and most deposit disputes fall well within that range.
Evidence that makes your demand letter credible
A demand letter without documentation is a request. A demand letter with documentation is a demand. Before you write a single word, gather the following.
Your lease, signed by both parties, confirms the deposit amount, the tenancy term, and any terms governing what the landlord could deduct. Your proof of payment for the deposit, whether that's a canceled check, a bank transfer record, or a move-in receipt, establishes the exact dollar amount at issue.
Move-in and move-out documentation is critical. Photos or video from both dates, with timestamps, give you a before-and-after record of the unit's condition. If you did a written move-in inspection with the landlord, bring that too. Any text, email, or letter you sent the landlord after move-out, particularly anything that includes or references a forwarding address, establishes when the 30-day clock started.
If the landlord sent an itemized statement, keep it. You'll use it to challenge each deduction individually. If they sent nothing, the absence of any written accounting within 30 days is itself evidence of a statutory violation under § 38-12-104.
Two copies of everything: one for your records, one to include with the demand letter if it goes to court.
How to write the Colorado deposit demand letter
The demand letter's job is to do three things at once: put the landlord on formal notice, cite the statute so they understand the legal exposure, and give them a clear path to resolve the dispute without court. Everything in the letter should serve one of those three purposes.
Start with a short header block: your name, current address, the rental address, the move-in and move-out dates, and the date you provided your forwarding address. This establishes the timeline in the first ten lines.
The body of the letter needs four components. State the amount of the deposit you paid and the date you paid it. State that the 30-day window under Colo. Rev. Stat. § 38-12-103 has passed (or will pass on a specific date) without a compliant return or itemized accounting. Name the liability under Colo. Rev. Stat. § 38-12-105: the wrongfully withheld amount, 12% annual interest from the date of the violation, and the right to attorney's fees. Then make a specific demand: return the full deposit (or a stated portion, if the landlord has a partial legitimate deduction) within 14 calendar days.
Close with a sentence that names the consequence: if payment isn't received by the stated deadline, you'll file in Colorado County Court small claims and seek the withheld amount, statutory interest, and all costs recoverable under § 38-12-105.
The tone should be factual and specific. Skip the adjectives. Skip the phrases like "egregious conduct" or "clear bad faith." Let the statute and the timeline do the work. A letter that reads like it was written by someone who knows the statute is more effective than one that reads like it was written by someone who is angry (even if both are true).
If the landlord doesn't respond
If your 14-day deadline passes without payment or a credible response, the next step is court. You can file a Colorado small claims case for a withheld deposit in the County Court covering the rental property. Colorado's small claims limit is $7,500, which is sufficient for most deposit disputes including accumulated interest and costs.
Filing in small claims doesn't require a lawyer, and the process is designed for self-represented plaintiffs. The demand letter you already sent becomes evidence in your favor: it shows you gave the landlord written notice of the violation, cited the statute, and allowed a reasonable cure period. Judges in Colorado County Court see deposit cases frequently, and a plaintiff who shows up with a demand letter, proof of certified mailing, and clear documentation of the 30-day window tends to have a short hearing.
What to expect after you send the letter
Most landlords respond within the 14-day window once the letter lands. The certified mail tracking creates a record of delivery. The statutory citation makes the legal exposure concrete. And the 12% interest plus attorney's fees provision gives the landlord an incentive to pay now rather than argue later.
A few common responses and how to handle them: the landlord sends partial payment, which you should accept while reserving the right to pursue the remaining balance. The landlord sends a belated itemized statement, which you review against your move-in documentation and respond to each contested item in writing. The landlord ignores the letter entirely, which is the clearest path to court and the most common fact pattern in a successful small claims judgment.
Colorado's 12% annual interest continues to accrue on any unpaid, wrongfully withheld amount until the landlord pays or the court enters judgment. That ongoing accrual creates a financial incentive for the landlord to resolve things quickly. It also means that waiting a few extra months before filing doesn't necessarily hurt your recovery, though prompt action signals seriousness.
Keep every piece of communication after the demand letter. Texts, emails, any oral conversations you can document. The landlord's conduct after receiving formal written notice is often the clearest evidence of whether the violation was willful under § 38-12-105.
Sources & further reading
Primary sources
We draft from authoritative statutes and state-court self-help guidance. Every article on Sue.com links to the primary source so you can verify the citation yourself.