Stage 1 fire restrictions, enacted for unincorporated areas of western Boulder County.

Tax Lien Sale Frequently Asked Questions

Tax Lien Sale Frequently Asked Questions

Auction list publishing schedule

The list of properties going to auction at the tax lien sale is published in the county newspaper of record 4 weeks prior to the sale for 3 consecutive weeks.

On the last week prior to the sale it is published in the:

Longmont Daily Times-Call (current paper of record)
Boulder Daily Camera
The Nederland Mountain Ear
The Lafayette News
The Louisville Times
The Lyons Recorder
The Colorado Daily

Obtaining copies of the auction list

Copies of the list will be available in the Treasurer’s Office at 1325 Pearl Street Boulder, Colorado, close to the time of the sale. A current list of properties will also be available on our website near the time of the sale and is updated daily once posted.

Sale location

Boulder County Courthouse
1325 Pearl Street
Third Floor
Boulder, CO 80302
Map & Directions


Registered bidders park for free in any of the 4 downtown city parking lots:

11th St. and Walnut St. Map & Directions
14th St. and Walnut St. Map & Directions
11th St. and Spruce St. Map & Directions
15th St. and Pearl St. Map & Directions

When you register, you will receive an 8 hour parking pass.

Where is information about property locations available?

You can look up parcel information using the Assessor’s Property Search tool. You will need the tax account number which is listed in bold in the advertisement or the property address.

Is ownership in the property transferred?

No. As a tax lien investor, you have no right, title or interest in the property. You have only purchased a lien against the property based on delinquent taxes.

Can the properties be inspected?

No. You are only purchasing a lien. The owner of the property retains all rights of ownership, title and privacy.

Are observers allowed at the tax lien sale?

Yes, but seating is limited. If the room is full, you may be asked to give up a seat to a registered bidder.

Registration Information

Registration opens at 7:30 AM on the day of the sale
The exact spelling of the name you register with will become the name used on the tax lien certificate
To register you will need to provide your:

  • Name
  • Address for checks & correspondence
  • Social Security or Tax ID number
  • Completed, signed IRS W-9 form

How long will the sale last?

The sale will begin as soon after 8:30 AM as all bidders are registered. The auction will last until all properties are sold or until 5:00 PM. Treasurer’s staff will determine if the sale will be continued or adjourned to the next business day. In recent years, the sale has not gone past 3:00 PM.

How is the interest rate determined?

The interest rate is determined in September. The rate is determined by the State of Colorado, and is set 9 percentage points above the discount rate at the Kansas City federal reserve bank, rounded up to the nearest whole percent.

How is interest calculated?

Interest is calculated monthly on the first day of the month.

Will there be an auctioneer?


Does the auction follow the list published in the newspaper?

Yes. The list is published in alphabetical order by owner name. Some property owners may pay their taxes between our advertisement and the tax lien sale, however, and will not be included.

How is the bidding done?

The auction is open bidding— we do not rotate through bidders in a predetermined order. The bid amount is the premium amount.

What is a Premium bid?

Premium bids are the amounts over and above the taxes, interest and fees listed on the day of sale list.

Is interest calculated on my premium bid?

No. You do not earn any interest on a premium bid.

Do I get my premium bid back?


What is the average premium bid?

For the last five years premium bids have averaged from 5% to 9%, although individual properties may go for more or less. Historically, in Boulder County, the vast majority of tax liens have sold for a premium bid.

How are premium bid monies used by county government?

Premium bid money goes directly to the County General Fund. Premium bid funds are not retained by the Treasurer’s Office.

Can I lose money investing in tax lien sales?

Yes, you can, if the interest you earn does not equal or exceed the premium bid amount you paid. This is a “buyer beware” process. You need to make informed bids.

As an example, if you place a premium bid of 6% and the redemption interest rate is 10%, you will lose money if the lien is redeemed before eight months pass.

Why are several items grouped together on the day of sale auction list?

The Treasurer may combine properties that are under the same ownership and sell those items as a group.

In terms of encumbrances, what position are tax liens?

Tax liens are a first, prior and perpetual lien against the property. The only lien ahead of a tax lien purchased this year is a prior year’s tax lien.

Can I find out what I’ve purchased during the sale?

A buyer balance sheet is available any time in the conference room.

What is a tax lien sale certificate of purchase?

A tax lien certificate is a legal document that names you as the holder of the lien and sets the interest rate.

Will I get the original tax lien sale certificate of purchase?

No, the Boulder County Treasurer retains all Tax Lien Sale Certificates of Purchase for safekeeping. Copies will be mailed to you within a week following the sale.

May I sell the tax lien sale certificates to another party?

Yes, tax lien certificates may be transferred to another party.

  • All certificates must be notarized
  • Each certificate must be recorded with the Boulder County Clerk and Recorder
  • There is a charge for recording each certificate
  • The new certificate holder must complete an IRS W-9 form

What is an endorsement of subsequent taxes?

If you hold a tax lien, and the property owner does not pay taxes in the next or following years, you have the option of adding those delinquent taxes to your certificate.

Do I have to pay subsequent taxes each year?

No. This is optional. If you do not endorse unpaid taxes, the property will be sold at the next tax lien sale.

Endorsement notification

In July, the Treasurer’s office will send you a notice of any certificates eligible for endorsement along with amounts due.

  • The amount includes an endorsement fee of $5 for each certificate endorsed
  • The endorsement fee is paid by the property owner when they redeem the property
  • The interest rate for endorsements is the rate of your original lien

How do property owners cure (redeem) a tax lien?

All tax lien sale redemptions must be made through the Treasurer’s office. Redemptions can be made at any time, and must be made in certified funds (cash, cashier’s check, money order). Redemptions will always include at least one month’s interest, as interest begins accruing immediately once liens are sold or endorsed.

Treasurer’s Deed

If the property owner does not pay property taxes for three years from the date of the original tax lien sale, you may request a Treasurer’s Deed.

  • The Treasurer’s Deed process may take six months to a year depending on circumstances
  • Successfully processed applications give you title to the property
  • Less than ½ of 1% of tax liens go to tax deed

Bankruptcy on tax lien properties

Properties in bankruptcy cannot be endorsed. The Treasurer’s Office monitors bankruptcies and collects taxes through the court. The properties are redeemed at the time of a bankruptcy sale.

Interest payments

Interest is only paid when a tax lien is redeemed. There are no other interest payments.

1099 reports to the IRS

1099 reports are filed with the IRS each year on redeemed properties.

Over-the-Counter Certificates

Boulder County does not offer tax lien certificates over the counter.

Contact Us

Treasurer's Office

Phone: 303-441-3520
Fax: 303-441-3598

Mailing Address

PO Box 471
Boulder, CO 80306


1325 Pearl St.
1st Floor
Map and Directions Boulder Location
Hours: 8 a.m. to 4:30 p.m.
Monday - Friday

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