Stage 1 Fire Restrictions, effective Aug. 12, 2025, for unincorporated western Boulder County.
Visit the Boulder County Ballot Measures website for information about possible 2025 ballot measures.
When submitting your real property appeal to the Boulder County Assessor’s Office, please keep in mind the following timelines, dates and processes.
Please note that the dates below reflect statutory deadlines. If a deadline falls on a Saturday, Sunday or a legal holiday, it is legally extended to the following business day. For example, if the June 1 deadline occurs on a weekend, then the deadline would be the following Monday. 39-1-120(3), C.R.S.
| Calendar Date | Assessor Appeal Deadline |
|---|---|
| Not later than May 1 | Assessor mails real property Notices of Valuation. |
| May 1 through June 9 | Assessor hears appeals to real property valuation. Mailed appeals must be postmarked on or before June 9. Appeals delivered in person will be accepted through 5 p.m. on June 9. Online and faxed appeals must be time-stamped no later than 11:59 p.m. on June 9 to be on time. Please be sure to allow enough time in the event that others are also submitting their appeals at the last minute. |
| On or before Aug. 15 | Assessor mails Notice of Determination on real property appeals. |
| On or before Sept. 15 | Taxpayer files a real property valuation appeal to the Board of Equalization (BOE). |
| Calendar Date | Assessor Appeal Deadline |
|---|---|
| Not later than June 15 | Assessor mails personal property Notices of Valuation. |
| June 15 through June 30 | Taxpayer submits appeals to personal property valuation. Mailed appeals must be postmarked on or before June 30. Appeals delivered in person will be accepted through 5 p.m., June 30. Online and faxed appeals will not be accepted if time-stamped after 11:59 p.m., June 30. Please be sure to allow enough time in the event that others are also submitting their appeals at the last minute. |
| June 15 through June 30 | Assessor hears appeals to personal property valuation. |
| After June 30 | Online and faxed appeals time-stamped after 11:59 p.m. June 30, mailed appeals postmarked, or appeals submitted after June 30 are LATE. Your property value will be reviewed, but by filing after June 30 you have forfeited the right to further appeal. |
| Not later than Aug. 15 | Assessor mails Notice of Determination for personal property appeals. |
| Not later than Sept. 15 | Taxpayer files a written personal property appeal to the Board of Equalization, (BOE). |
| Calendar Date | Assessor Appeal Deadline |
|---|---|
| Not later than Nov. 1 | BOE concludes hearings on property valuation appeals. |
| Within 5 days of rendering BOE decision | BOE mails decisions on real and personal property appeals. |
| Not later than 30 days after BOE decision | Appeals from BOE decisions must be filed with the Board of Assessment Appeals, district court, or the Board of County Commissioners for binding arbitration. |
Please note that if a deadline falls on a Saturday, Sunday or a legal holiday, it is legally extended to the following business day. For example, if the June 1 deadline occurs on a weekend, then the deadline would be the following Monday. 39-1-120(3), C.R.S.
Phone: 303-441-3530
Fax: 303-441-4996
PO Box 471
Boulder, CO 80306-0471
Hours: 7:30 a.m. to 5 p.m.
Monday-Thursday
Closed Friday
Assessor Boulder and Longmont Drop Boxes
1325 Pearl St., 2nd floor
Boulder, CO 80302
Hours: 7:30 a.m. to 5 p.m.
Monday-Thursday
Map and Directions Boulder Location
515 Coffman St., Suite 114
Hours: 7:30 a.m. to 5 p.m.
Monday only
Map and Directions Longmont Location
1755 S Public Road
Hours: 7:30 a.m. to 5 p.m.
Tuesday only
Map and Directions Lafayette Location
