Boulder County property record for 140 S 42nd St, Boulder, CO 80305
| Property Type | Single Family Home |
|---|---|
| Details | 3 bd · 1.75 ba · 1,400 sqft · built 1960 |
| Lot Size | 0.164 acres (7,163 sqft) |
| Owner | Individual Name on File |
| Last Sale | $70,100 (Jun 1979) |
| Tax Bill | $4,221 (2025) |
| Flood Zone | Zone X (minimal risk) |
| APN | 1577-05-4-09-005 |
| Primary APN | 1577-05-4-09-005 |
|---|---|
| Alternative APNs |
|
| Bedrooms | 3 Beds |
|---|---|
| Full Baths | 1.75 Baths |
| Half Baths | 1 Half Bath |
| Total Rooms | 5 Rooms |
| Stories | 1 Story |
| Building Area | 1,400 sqft Living Area |
| Gross Area | 2,800 sqft |
| 1st Floor Area | 1,400 sqft |
| Basement Area | 1,400 sqft |
| Interior Walls | Wallboard/Drywall |
| Year Built | Built 1960 |
|---|---|
| Effective Year Built | Effective 1960 |
| Architectural Style | Ranch |
| Exterior Material | Brick Veneer |
| Construction Type | Masonry / Concrete Block |
| Lot Area | 7,163 sqft (0.164 acres) |
| Garage Type | Carport |
| Garage Area | 312 sqft |
| Carport | Carport |
| Carport Area | 312 sqft |
| Parking Spaces | 1 Parking Space |
| Patio Area | 240 sqft |
| Heating System | Forced Air with A/C |
|---|
| Account Number | R0009475 |
|---|---|
| Street Address | 140 S 42ND ST |
| City | BOULDER |
| State | CO |
| Zip | 80305-5537 |
| Property Category | Residential |
| Property Type | Residential > Single Family > Home |
| Legal Description | LOT 5 BLK 12 WILLIAM MARTIN HOMESTEAD |
| Legal Range | 70 |
| Legal Township | 1S |
| Legal Section | 05 |
| Legal Subdivision | WILLIAM MARTIN HOMESTEAD - BO |
| Legal Block | 12 |
| Legal Lot Number | 5 |
| Jurisdiction | BOULDER CO |
| Township / Civil Division | BOULDER |
| Census Block Group | 1 |
| Census Block | 1018 |
| Census Tract | 12507 |
140 S 42nd St is owned and occupied by an individual who acquired it in June 2000.
Source: Boulder County records, as of September 18, 2026
| Owner of Record | Individual Name on File |
|---|---|
| Mailing Address | 140 S 42ND ST, BOULDER, CO 80305-5537 |
| 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 | Jun 25, 1979 · Amount on File |
| Deed Sale | Jun 25, 1979 · Amount on File |
| Prior Sale | Sep 16, 1975 · Amount on File |
| Deed Document Number | 1979344421 |
| Last Transfer Date | Jun 15, 2000 |
| Transfer Doc | 0002056631 |
| Record Updated | Oct 29, 2026 |
The 2025 property tax bill for 140 S 42nd St was $4,221.
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 | $50,211 (-0.62%) Land $33,211 Building $17,000 | $808,400 (-) Land $558,400 Building $250,000 | |
| 2025 | $4,221.00 | $50,525 Land $34,900 Building $15,625 | $808,400 Land $558,400 Building $250,000 |
| 2023 | $4,119.00 (+14.64%) | $58,089 (+27.27%) Land $40,897 Building $17,192 | $867,000 (+32.02%) Land $610,400 Building $256,600 |
| 2022 | $3,593.00 | $45,641 Land $30,337 Building $15,304 | $656,700 Land $436,500 Building $220,200 |
Assessed value and assessed market value are set for property tax purposes and are not market price estimates.
FEMA maps place 140 S 42nd St in Zone X, an area of minimal flood risk, though there have been 16 flood claims nearby since 1995.
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 minimal risk |
|---|---|
| Flood Insurance Requirement | Not required lenders may require it |
| Flood Insurance Cost | Premium on File median of 25 policies |
| Community Rating System | Class 5 (25% premium discount) |
| Nearby Flood Policies | 25 in force |
| Nearby Flood Claims | 16 (1995–2013) |
| Claims Outside the SFHA | 2 of 16 |
| 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 140 S 42nd St is low, with a 0.01% annual chance of wildfire.
Source: USDA Forest Service Wildfire Risk to Communities (2nd edition), as of 2024
| Wildfire Risk | Low lower than 80% of the US · lower than 91% of Colorado |
|---|---|
| Wildfire Likelihood | 0.01% annual chance |
| Exposure | None beyond 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 678 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: AT&T.
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