Boulder County property record for 365 21st St, Boulder, CO 80302
| Property Type | Single Family Home |
|---|---|
| Details | 3 bd · 1.5 ba · 1,218 sqft · built 1954 |
| Lot Size | 0.232 acres (10,103 sqft) |
| Owner | Individual Name on File |
| Tax Bill | $6,903 (2025) |
| Flood Zone | Zone X (moderate risk) |
| APN | 1577-06-1-10-009 |
| Primary APN | 1577-06-1-10-009 |
|---|---|
| Alternative APNs |
|
| Bedrooms | 3 Beds |
|---|---|
| Full Baths | 1.5 Baths |
| Half Baths | 1 Half Bath |
| Total Rooms | 5 Rooms |
| Stories | 1 Story |
| Building Area | 1,218 sqft Living Area |
| 1st Floor Area | 1,218 sqft |
| Interior Walls | Wallboard/Drywall |
| Year Built | Built 1954 |
|---|---|
| Effective Year Built | Effective 1954 |
| Architectural Style | Ranch |
| Exterior Material | Brick Veneer |
| Construction Type | Frame |
| Roof Material | Asphalt |
| Lot Area | 10,103 sqft (0.232 acres) |
| Garage Type | Detached |
| Garage Area | 440 sqft |
| Parking Spaces | 2 Parking Spaces |
| Porch | Porch |
| Porch Area | 54 sqft |
| Patio Area | 754 sqft |
| Cooling System | Central |
|---|---|
| Heating System | Forced Air with A/C |
| Account Number | R0008557 |
|---|---|
| Street Address | 365 21ST ST |
| City | BOULDER |
| State | CO |
| Zip | 80302-8012 |
| Property Category | Residential |
| Property Type | Residential > Single Family > Home |
| Legal Description | LOT 10 & N 2 FT LOT 11 BLK 16 & ALLEY ADJ INTERURBAN PARK |
| Legal Range | 70 |
| Legal Township | 1S |
| Legal Section | 06 |
| Legal Subdivision | INTERURBAN PARK - BO |
| Legal Block | 16 |
| Legal Lot Number | 10 |
| Jurisdiction | BOULDER CO |
| Township / Civil Division | BOULDER |
| Census Block Group | 1 |
| Census Block | 1025 |
| Census Tract | 12505 |
365 21st St is owned and occupied by an individual who acquired it in November 1987.
Source: Boulder County records, as of September 18, 2026
| Owner of Record | Individual Name on File |
|---|---|
| Mailing Address | 365 21ST ST, BOULDER, CO 80302-8012 |
| Occupancy | Owner Occupied |
| Owner Type | Individual |
Owner names and exact recorded amounts are on file and can be viewed instantly on this page with a free 10-day trial.
| Deed Names | Name on Deed |
|---|---|
| Last Sale | Nov 3, 1987 |
| Deed Sale | Nov 3, 1987 |
| Prior Sale | Aug 30, 1985 · Amount on File |
| Deed Document Number | 1987886766 |
| Record Updated | Oct 29, 2026 |
The 2025 property tax bill for 365 21st St was $6,903.
Source: Boulder County assessment roll, as of September 18, 2026
| Type | Name |
|---|---|
| State | Colorado |
| County | Boulder County |
| Municipality | Boulder City |
| Unified School District | Boulder Valley School District RE-2 (PK - 12) |
| Year | Tax Bill | Assessed Value | Assessed Market Value |
|---|---|---|---|
| 2026 | $80,818 (+2.75%) Land $71,454 Building $9,364 | $1,258,500 (-) Land $1,120,800 Building $137,700 | |
| 2025 | $6,903.00 | $78,656 Land $70,050 Building $8,606 | $1,258,500 Land $1,120,800 Building $137,700 |
| 2023 | $5,969.00 (+5.29%) | $79,509 (+16.92%) Land $71,375 Building $8,134 | $1,186,700 (+21.28%) Land $1,065,300 Building $121,400 |
| 2022 | $5,669.00 | $68,005 Land $58,477 Building $9,528 | $978,500 Land $841,400 Building $137,100 |
Assessed value and assessed market value are set for property tax purposes and are not market price estimates.
FEMA maps place 365 21st St in Zone X, an area of moderate flood risk, within 500 ft of a high-risk flood zone.
Source: FEMA National Flood Hazard Layer, effective October 14, 2026 · OpenFEMA NFIP redacted claims and policies, as of September 2026
| FEMA Flood Zone | Zone X moderate risk |
|---|---|
| 500-Year Floodplain | Yes 0.2% annual chance |
| Nearest Special Flood Hazard Area | Zone AE, within 500 ft |
| Flood Insurance Requirement | Not required lenders may require it |
| Flood Insurance Cost | Premium on File median of 15 policies |
| Community Rating System | Class 5 (25% premium discount) |
| Nearby Flood Policies | 15 in force |
| Nearby Flood Claims | 12 (1994–2013) |
| Claims Outside the SFHA | 4 of 12 |
| Most Recent Claim | Sep 2013 · Severe Storms, Flooding, Landslides, And Mudslides |
| Claims by Event |
|
Values are read at the parcel center point; flood claims are located to the census block group, not this parcel; lenders make the official flood determination.
Wildfire risk around 365 21st St is moderate, ranking above 67% of the US, with a 0.2% annual chance of wildfire.
Source: USDA Forest Service Wildfire Risk to Communities (2nd edition), as of 2024
| Wildfire Risk | Moderate above 67% of the US · above 59% of Colorado |
|---|---|
| Wildfire Likelihood | 0.2% annual chance |
| Exposure | Indirect within ember reach |
Values cover an area roughly 900 ft across, not the parcel itself; insurers use their own ratings.
Source: EPA Safe Drinking Water Information System, as of September 2026
| Water System | CITY OF BOULDER serves 166,080 people · EPA ID CO0107152 |
|---|---|
| Water Source | Surface water |
| Last State Inspection | Sep 2024 |
| Lead | 2 ppb (2023–2025) action level 15 ppb |
| Water Quality | Haloacetic acids resolved · Jul 2017 |
|---|---|
| Treatment and Procedure | None last 10 years |
| Monitoring and Reporting | 1 last 3 years |
Results are for the whole water system, not water tested at this address; lead at the tap also depends on the building's own pipes.
Source: FCC Broadband Data Collection, based on 481 locations within half a mile, as of December 31, 2025
| Provider | Max Down / Up (Mbps) |
|---|---|
| Ayva Networks Fixed Wireless | 2,500 / 2,500 |
| CenturyLink Fiber · DSL in parts of the area | 2,000 / 1,000 |
| Xfinity Cable | 2,000 / 250 |
| Verizon Fixed Wireless | 300 / 20 |
| LiveWireNet Fixed Wireless | 250 / 100 |
| T-Mobile Fixed Wireless | 100 / 20 |
May also be available: Magnolia Road Internet Cooperative.
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