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.

Boulder County government offices closed Monday, Sept. 1, in observance of Labor Day.

2021 Time Trend Adjustments

2021/2022 Comparable Sales

Using Time Trending for Property Valuation

Residential Time Trends July 1, 2015 through June 30, 2020

Market Area Factor Tables
2021 Apartment Time Trends
Market Areas: 640, 641, 642, 643, 644, 645
PDF XLSX
2021 Condominium Residential Time Trends
Market Areas: 630, 632, 633, 634
PDF XLSX
2021 Boulder Residential Time Trends
Market Areas: 101, 102, 103, 104, 105, 106, 107, 108, 109
PDF XLSX
2021 Erie, Gunbarrel, Lafayette, Louisville, Niwot, & Superior Residential Time Trends
Market Areas: 401, 402, 403, 404, 405, 407, 501
PDF XLSX
2021 Longmont Residential Time Trends
Market Areas: 502, 503, 504, 505, 506, 507
PDF XLSX
2021 Mountain Residential Time Trends
Market Areas: 201, 202
PDF XLSX
2021 Unincorporated Plains Residential Time Trends
Market Areas: 301, 302, 303, 304
PDF XLSX

Contact Us

Assessor

Phone: 303-441-3530
Fax: 303-441-4996

Email

Mailing Address

PO Box 471
Boulder, CO 80306-0471

Hours: 7:30 a.m. to 5 p.m.
Monday-Thursday
Closed Friday

Locations

Assessor Boulder and Longmont Drop Boxes

Boulder

1325 Pearl St., 2nd floor
Boulder, CO 80302
Hours: 7:30 a.m. to 5 p.m.
Monday-Thursday
Map and Directions Boulder Location

Longmont

515 Coffman St., Suite 114
Hours: 7:30 a.m. to 5 p.m.
Monday only
Map and Directions Longmont Location

Lafayette

1755 S Public Road
Hours: 7:30 a.m. to 5 p.m.
Tuesday only
Map and Directions Lafayette Location