Boulder, Colorado Security Deposit: Which Rule Applies and Your Next Step
The Boulder ordinance text reviewed here does not change the return deadline: Colorado law gives 30 days (C.R.S. 38-12-103 and 38-12-104). The city adds interest rules (BRC §§ 12-2-2, 12-2-5, 12-2-7 (Ord. 7320)). Check whether the ordinance covers your rental, then enter your dates and deposit below for a state law calculation and a letter.
State law vs Boulder ordinance
| Rule | Colorado state law | Boulder ordinance |
|---|---|---|
| Return deadline | 30 days after Termination of the lease or surrender and acceptance of the premises, whichever occurs last. 60 days after Termination of the lease or surrender and acceptance of the premises, whichever occurs last. lease specifies a longer period (statute max 60 days). | No separate return deadline in the ordinance text reviewed here |
| Interest | No statewide interest requirement in the verified data. | Simple interest on the full amount of residential security deposits (including pet deposits; not last month's rent held as such). Rate is the city manager's average of one-year CD rates at three Boulder banks as of December 15, published for the following calendar year. 2026 rate is 2.08%. Rate in effect at lease signing applies for that term; month-to-month resets each January 1. (BRC §§ 12-2-2, 12-2-5, 12-2-7 (Ord. 7320)) |
| Penalty | Treble (3x) the amount of the security deposit portion wrongfully withheld, plus reasonable attorney fees and court costs. As of the 2026 amendment (HB25-1249), 'willful' retention was replaced with 'wrongful' retention as the trigger (C.R.S. 38-12-103(3)(a)), and a landlord is deemed to have wrongfully withheld a deposit if the landlord: (a) fails to timely provide the written statement/documentation, (b) provides a statement that fails to list exact reasons, (c) fails to return the difference owed within the deadline, or (d) retains the deposit 'in bad faith' (defined in new subsection (3.5) as retaining an amount that unreasonably exceeds actual damages - presumed if 125%+ of actual damages - retained without actual cause, an amount the landlord knew/should have known exceeded actual damages, or retained for an unlawful/retaliatory/discriminatory purpose). Tenant must first give the landlord written notice/demand and 7 days' notice of intent to sue before filing; treble damages/attorney fees are only recoverable if the landlord fails to return the full deposit or withheld portion within 7 days of that demand (new subsection (3)(c)). If a landlord retained in good faith, complied with all requirements, but a court finds the retained amount exceeded actual damages, liability is limited to the excess amount plus court costs only (no treble damages) - new subsection (3.5)(d). Bad faith required: Yes. | Willful wrongful retention of interest: tenant may recover treble damages or $100, whichever is greater, plus attorney's fees and court costs, after at least seven days' written notice to the landlord. (BRC § 12-2-6(c)) |
| Who it covers | See state statute and conditions above | Residential security deposits in the City of Boulder. Mobile home parks are not covered. Waiver of the interest right is void (BRC § 12-2-8). |
C.R.S. 38-12-103 and 38-12-104 (Colorado Security Deposit Refund Act, Title 38, Article 12, Part 1); as amended by HB25-1249, effective January 1, 2026 · Boulder Revised Code Chapter 12-2, Landlord-Tenant Relations (security deposit interest requirement, §§12-2-4 to 12-2-7)
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Details of the return rules
| When it applies | Deadline | Starts from |
|---|---|---|
| No, or my lease doesn't say | 30 days | Termination of the lease or surrender and acceptance of the premises, whichever occurs last |
| Yes, my lease says the landlord has more time (the law caps it at 60 days) | 60 days | Termination of the lease or surrender and acceptance of the premises, whichever occurs last |
Colorado return rule: 30 days. Check the dates you entered above.
What Boulder adds to your claim
- interest: Simple interest on the full amount of residential security deposits (including pet deposits; not last month's rent held as such). Rate is the city manager's average of one-year CD rates at three Boulder banks as of December 15, published for the following calendar year. 2026 rate is 2.08%. Rate in effect at lease signing applies for that term; month-to-month resets each January 1. (BRC §§ 12-2-2, 12-2-5, 12-2-7 (Ord. 7320))
- penalty: Willful wrongful retention of interest: tenant may recover treble damages or $100, whichever is greater, plus attorney's fees and court costs, after at least seven days' written notice to the landlord. (BRC § 12-2-6(c))
County small claims courts
| County | Court and city | Limit | Filing fee | E-filing | Court link |
|---|---|---|---|---|---|
| Boulder County | Boulder County Court (Small Claims Division, 20th Judicial District), Boulder | $7,500 (statewide) | Statewide filing fee: $31 (claims up to $500) to $55 (claims $500-$7,500) - statewide small claims fee schedule | No | Official court website Court page check not recorded |
See the Boulder County county filing page
Statute says
Under Boulder Revised Code §12-2-5, the tenant is the owner of the security deposit. Tenants cannot agree to give up this right in the lease contract. The landlord is responsible for paying interest on the security deposit at the end of the lease. This interest is calculated as simple interest.
What this means
City code makes the tenant the owner of the security deposit and requires simple interest at a city-manager rate (average one-year CD at three Boulder banks, reset each December 15). Interest is due within one month after the lease ends. Wrongful withholding of interest yields treble damages or $100, whichever is more, plus attorney fees after a seven-day written demand.
Source accessed: .
FAQ
Does Boulder set a separate deposit return deadline?
The ordinance text reviewed here sets no separate return deadline. See the Colorado deadline and its conditions above.
What else does the Boulder ordinance require?
City code makes the tenant the owner of the security deposit and requires simple interest at a city-manager rate (average one-year CD at three Boulder banks, reset each December 15). Interest is due within one month after the lease ends. Wrongful withholding of interest yields treble damages or $100, whichever is more, plus attorney fees after a seven-day written demand.
Does the ordinance cover my rental?
Residential security deposits in the City of Boulder. Mobile home parks are not covered. Waiver of the interest right is void (BRC § 12-2-8).
What's next?
Previous page summary
City code makes the tenant the owner of the security deposit and requires simple interest at a city-manager rate (average one-year CD at three Boulder banks, reset each December 15). Interest is due within one month after the lease ends. Wrongful withholding of interest yields treble damages or $100, whichever is more, plus attorney fees after a seven-day written demand.