Colorado's Tax Lien Rate Is a Formula, Not a Number: 11,076 Parcels Owe $54.1M

Colorado is a tax lien state. County treasurers sell certificates of purchase at annual auctions, usually in October or November, and the buyer holds a lien rather than the property. That is the short answer. The part that catches people out is the rate: Colorado does not have one. It has a formula that produces a new number every September, and if somebody quotes you a fixed Colorado rate in August they are quoting last year's. Underneath the statute sits the file - 11,076 priced tax-delinquent parcels across 6 Colorado counties, carrying $54,140,837.75 in unpaid taxes.

So which is it, tax lien or tax deed?

A lien. Colorado counties sell tax lien certificates at annual online auctions. The certificate is a lien on the delinquent parcel that accrues interest; it is not title, and it does not let you enter, rent or improve the property.

Four facts define the Colorado version of that arrangement:

1. Sales are annual, typically October or November. Registration usually opens in late September. Realauction, SRI Incorporated and county treasurer portals host them.
2. Bidding is premium, not bid-down. Liens go to whoever pays the highest premium above the taxes, interest and costs owed. Ties and no-premium lots are settled by rotational or random selection in some counties.
3. Three years before a treasurer's deed. After three years, an unredeemed certificate holder may apply for a treasurer's deed.
4. Redemption stays open until the deed is actually executed. So the practical window can run past three years, and the certificate itself stays valid for up to 15.

Put those together and Colorado reads as a yield instrument with a long tail, not an acquisition play. The ordinary outcome is redemption with interest.

The rate is a formula, and this year's number does not exist yet

This is the part of Colorado most worth understanding, because every other lien state in this series has a rate you can write on a card. Nebraska pays a fixed 14%. Kentucky pays a fixed 12%. Colorado pays whatever the formula produces.

Under C.R.S. 39-12-103(3), the redemption interest rate is set annually at 9 percentage points above the federal reserve discount rate in effect on September 1, rounded to the nearest full percent. The 2025 sale rate was 14%. The rate for the 2026 sales is not set until September 1, 2026, which had not happened when this page was written on 24 August 2026 - so this page does not print a 2026 number, and you should be suspicious of any page that does.

Two practical consequences. First, a Colorado certificate bought in a high-rate year keeps that year's rate for its life, so the vintage of your certificate matters as much as the parcel. Second, you cannot model a Colorado portfolio at a single blended rate the way you can in a fixed-rate state; each year's cohort earns its own number.

The premium is the trap

Colorado's bidding is premium, which means you compete by handing over more cash up front. The catch is written into the redemption statute: only the taxes-and-costs base accrues interest. The premium you pay above that base earns nothing, and it is not refunded when the owner redeems. It is gone.

So the premium is not a price - it is a permanent write-down of your yield, applied at the moment you win. A certificate bought at a 20% premium on a base earning 14% returns materially less than 14%, and a large enough premium can turn a redemption into a loss. Subsequent taxes you endorse onto the certificate do earn the rate, which is where a good part of the real return comes from.

Read that next to the file and the discipline becomes obvious. The median Colorado parcel in our data owes $1,234.99, while the average owes $4,888.12 - the average is four times the median because a small number of very large debts pull it up. Bidding a flat premium across a file shaped like that overpays badly on the small end.

How many Colorado properties are actually tax delinquent?

Here is our count, read from the live county database on 24 August 2026:

• 11,077 tax-delinquent parcels in our Colorado file, of which 11,076 carry a dollar amount owed
• 6 Colorado counties with priced delinquent records, out of the 64 counties in the state
• $54,140,837.75 owed in total across those records
• $4,888.12 average owed per parcel, against a measured median of $1,234.99
• $25.62 on the smallest debt in the file, and $958,027.00 on the largest
• 9,892 of the records carry a street-numbered address; the other 1,185 are identified by parcel number only, and none are blank

A property counts as delinquent here when the county's own file shows money owed on it. Colorado is unusual in this series for holding no padding at all: we hold 11,077 Colorado parcel records in total and 11,077 of them are delinquent records. There is no full parcel roll sitting behind the number inflating it.

Every one of the 6 counties prices cleanly, and the file reconciles exactly. The 6 per-county queries sum to 11,077, and the county counter that drives the storefront reports 11,077 for Colorado. The two agree to the parcel. That is not a given: on the same day this page was written we re-measured a state whose counter advertises 14,165 delinquent parcels across all 55 of its counties while not one of the underlying records carries an amount owed. Counts without amounts cannot honestly be summed or averaged, and we do not build pages on them.

Colorado is a big-ticket file

The distribution of the 11,076 priced records, read straight from the file:

Amount owed	Parcels	Share of parcels
Under $500	4,283	38.7%
$500 to $1,999	2,322	21.0%
$2,000 to $4,999	2,736	24.7%
$5,000 and up	1,735	15.7%

The four bands sum to 11,076 parcels, which is every priced record in the file.

The 1,735 parcels owing $5,000 or more are 15.7% of the file and hold $41,461,821.19 - 76.6% of every dollar owed in Colorado. That is the most concentrated file in this series by a wide margin. In Kentucky 91% of parcels owe under $1,000 and the whole state totals $6.3M; Colorado's top sixth alone carries $41.5M.

It matters because premium bidding and a big-ticket file interact badly. Where the debts are large, the competition is heaviest and the premiums bid are largest, and the premium earns nothing. The cheap end of a Colorado file - 4,283 parcels under $500 - attracts less premium precisely because the certificates are small, which is where the stated rate is most likely to survive contact with the auction.

Where the delinquency actually sits

All six counties in our Colorado file, as of 24 August 2026:

County	Delinquent parcels	Total owed	Median owed
Denver County	8,368	$36,334,766.13	$876.14
Arapahoe County	1,326	$9,712,814.63	$2,472.13
Douglas County	896	$6,693,238.89	$3,428.18
Rio Grande County	312	$296,178.29	$320.04
San Miguel County	159	$1,089,134.69	$2,599.45
Mineral County	15	$14,705.12	$568.55

Denver alone holds 8,368 of the 11,076 priced parcels - 75.6% of the file - and $36,334,766.13, or 67.1% of the dollars. Add Arapahoe and Douglas and the three Front Range counties account for 95.6% of the parcels and 97.4% of the money. In practice, a Colorado strategy built on our data is a Denver metro strategy with three small mountain and valley files attached.

The county medians tell you these are different markets, not one market at different sizes. Denver's median parcel owes $876.14; Douglas County's owes $3,428.18, nearly four times as much, on a file one ninth the size. Rio Grande, down in the San Luis Valley, has a median of $320.04 and 193 of its 312 parcels owe under $500. Same statute, same rate, three completely different underwriting problems.

The extremes are worth naming. The largest single debt in the state, $958,027.00, sits in Douglas County. Arapahoe holds a $741,314.84 parcel and Denver a $522,208.84 one. Mineral County, with 15 delinquent parcels totalling $14,705.12, is the whole opposite end: the entire county file is smaller than one Denver parcel.

What this means if you are actually bidding

Put the statute and the file together and Colorado reads as a premium-discipline market:

• Your yield is set by what you overpay, not by the statute. The rate is fixed by formula once a year and cannot be bid down. What competition takes from you is the premium, and the premium earns nothing and is never returned. Every dollar of premium is a dollar of yield deleted before you start.
• Know which year's rate you are buying. The number resets each September 1 at 9 points over the federal discount rate, so a 2026 certificate and a 2024 certificate are different instruments. Do not model a portfolio at one blended rate.
• Underwrite three years, and then some. A treasurer's deed is not available for three years, redemption stays open right up until that deed is actually executed, and the certificate remains valid for up to 15 years. Capital committed here should be capital you do not need back.
• Endorsements are part of the return. Subsequent taxes you pay and endorse onto the certificate accrue at the same rate. In a state where premium eats the headline yield, the endorsement stream is a larger share of the answer than investors expect.
• Decide whether you are in Denver or not. 95.6% of the parcels and 97.4% of the dollars in our file sit in Denver, Arapahoe and Douglas. The three small files - Rio Grande, San Miguel and Mineral - total 486 parcels between them. There is no wide statewide sweep available in Colorado the way there is in Nebraska or Arkansas.

What we actually hold for Colorado

6 of Colorado's 64 counties, priced, as of 24 August 2026 - 11,077 delinquent parcels carrying $54,140,837.75. This is a deep file, not a wide one, and it is worth being plain about that: 58 Colorado counties are not in our delinquent file at all. If your target is Pueblo, Weld, Boulder, El Paso or Mesa, we do not have it today.

Two honest notes about using what is there.

The first is addresses. 9,892 of the records carry a street-numbered address and 1,185 identify the property by parcel number only; none are blank. That split is not spread evenly - it is almost entirely one county. Every one of Denver's 8,368 records carries a street address. Every one of Douglas County's 896 records does not, arriving as "Parcel R0448254, DOUGLAS County, CO" and nothing more. Arapahoe is 199 parcel-only out of 1,327, San Miguel 57 of 159, Rio Grande 31 of 312, Mineral 2 of 15. Bidding works from a parcel number either way; mailing an owner does not, and in Douglas County you cannot mail anyone from this file without a separate lookup.

The second is browsing, and here Colorado is clean: all 6 counties are published for county-by-county browsing. The statewide figure and the storefront describe exactly the same thing.

Create a free account to work with the data, or browse the Colorado county directory, the largest file in the state at Denver County, or the highest-value one at Douglas County.

Colorado tax sale questions

Is Colorado a tax lien or tax deed state?

Colorado is a tax lien state. County treasurers sell certificates of purchase at annual auctions, not deeds. The certificate is a lien against the parcel that accrues interest, not ownership of the property.

What interest rate does a Colorado tax lien pay?

It changes every year. The rate is set annually at 9 percentage points above the federal reserve discount rate in effect on September 1, rounded to the nearest full percent, under C.R.S. 39-12-103(3). The 2025 sale rate was 14%. The rate for the 2026 sales is fixed on September 1, 2026, so as of 24 August 2026 there is no 2026 figure to quote.

When are Colorado tax lien sales held?

Annually, once a year, typically in October or November. Registration usually opens in late September. Sales run through Realauction, SRI Incorporated and county treasurer online portals.

How does bidding work at a Colorado tax lien sale?

Premium bidding. Liens are struck to whoever pays the highest premium above the taxes, interest and costs owed, and ties or no-premium lots are resolved by rotational or random selection in some counties. The premium is not refunded on redemption and earns no interest, so bidding large premiums directly reduces your effective yield.

Does the premium I bid earn interest in Colorado?

No. Only the taxes-and-costs base accrues redemption interest. The premium above that base earns nothing and is never refunded when the owner redeems, which is why a high premium can turn a nominally 14% certificate into a low-single-digit return.

How long is the redemption period in Colorado?

Three years from the date of the tax lien sale before a treasurer's deed can be applied for. Redemption is allowed at any time before that deed is actually executed, so the practical window can exceed three years, and the certificate stays valid for up to 15 years.

Can I end up owning the property in Colorado?

Only after the three-year period, and only by applying for a treasurer's deed. Redemption remains open until the deed is executed. A Colorado certificate is a lien, not a purchase, and the ordinary outcome is redemption with interest.

How many tax delinquent properties are there in Colorado?

11,077 tax-delinquent parcels across 6 of Colorado's 64 counties as of 24 August 2026, of which 11,076 carry a dollar amount, totalling $54,140,837.75 - an average of $4,888.12 and a median of $1,234.99. A property counts as delinquent when the county's own file shows money owed on it.

Which Colorado county has the most tax delinquent property?

Denver County, with 8,368 delinquent parcels owing $36,334,766.13. That is 75.6% of the priced parcels in our Colorado file and 67.1% of the dollars. Arapahoe County is second with 1,326 parcels and Douglas third with 896 - though Douglas carries the highest median debt in the state at $3,428.18.

How big is a typical Colorado tax debt?

The median is $1,234.99 and the average is $4,888.12, the gap between them caused by a small number of very large debts. 38.7% of parcels owe under $500, while the 15.7% owing $5,000 or more hold 76.6% of all the money. The smallest debt in the file is $25.62 and the largest is $958,027.00.

Which Colorado counties does LienSuite cover?

Six - Denver, Arapahoe, Douglas, Rio Grande, San Miguel and Mineral - in the database, priced, as of 24 August 2026. All six are published for county-by-county browsing, and every one contributes real dollars rather than a count with no amount behind it. The other 58 Colorado counties are not in our delinquent file today.

Where these numbers come from

Every parcel count, average, median and dollar figure on this page was read from LienSuite's live county database on 24 August 2026, aggregated from 206 county sources and refreshed on an ongoing basis. "Tax delinquent" means the county's own file shows money owed on the property. Colorado carries no full parcel roll in our data, so the 11,077 figure is the whole of what we hold for the state, not a filtered subset of a larger number.

The statewide figures are sums of per-county queries, not estimates. All 6 Colorado counties in our file were queried individually and every one returned parcels with real dollar amounts owed. The per-county sums reconcile exactly against the county counter that drives the storefront: both report 11,077. The 64-county denominator is read from our own county tracking table, which lists 64 Colorado counties, 6 of which carry delinquent inventory.

The four owed bands sum to 11,076 records, which is 100% of the priced file. One Arapahoe record is flagged delinquent by years outstanding but carries no amount, which is why the parcel count is 11,077 and the priced count is 11,076; every dollar figure on this page is computed over the 11,076. The statewide median of $1,234.99 is a true median measured across the whole state in a single pass, not a combination of county medians, and the quartiles are $329.12 and $3,400.73.

Of the 11,077 records, 9,892 carry a street-numbered address and 1,185 identify the property by parcel number only; none are blank. The city field is empty on all of them, because these counties supply the locality inside the address line rather than as a separate field. Figures move as counties publish new rolls, and the county data behind this page was last refreshed on 24 August 2026. If you believe a figure here is wrong, write to [email protected] and we will check it against the source file.

This article is for informational purposes only and is not legal, tax, or investment advice. Colorado tax lien sales, redemption and treasurer's deeds are governed by Colorado Revised Statutes Title 39, Article 11 (sale of tax liens) and Article 12 (redemption), and both statute and county practice change over time. The redemption interest rate is reset annually under C.R.S. 39-12-103(3). Always confirm the current rate and procedure with the county treasurer, and consult a licensed Colorado attorney before bidding.