170 S 42nd St, Boulder, CO 80305 Property Records

Boulder County property record for 170 S 42nd St, Boulder, CO 80305

Property Summary

Property Type	Single Family Home
Details	4 bd · 2.25 ba · 2,038 sqft · built 1960
Lot Size	0.157 acres (6,824 sqft)
Owner	Individual Name on File
Last Sale	$975,000 (Jun 2026)
Tax Bill	$5,748 (2025)
Deeds & Mortgages	Jun 2026 Sale & Mortgage Mar 2023 Line of Credit
Flood Zone	Zone X (minimal risk)
APN	`1577-05-4-09-002`

Property Details

APN / Parcel Number

Primary APN	`1577-05-4-09-002`
Alternative APNs	`R0013139` `0013139`

Interior

Bedrooms	4 Beds
Full Baths	2.25 Baths
Half Baths	2 Half Baths
Total Rooms	7 Rooms
Building Area	2,038 sqft Living Area
Gross Area	2,291 sqft
1st Floor Area	1,762 sqft
Basement Area	276 sqft
Finished Basement	276 sqft
Interior Walls	Wallboard/Drywall

Exterior

Year Built	Built 1960
Effective Year Built	Effective 1989
Architectural Style	Split Level
Exterior Material	Brick Veneer
Construction Type	Masonry / Concrete Block
Roof Material	Asphalt
Lot Area	6,824 sqft (0.157 acres)
Garage Type	Attached
Garage Area	253 sqft
Parking Spaces	1 Parking Space
Porch	Porch
Porch Area	172 sqft
Deck Area	264 sqft

Utilities, Heating & Cooling

Cooling System	Central
Heating System	Forced Air with A/C

Location & Zoning

Account Number	R0013139
Street Address	170 S 42ND ST
City	BOULDER
State	CO
Zip	80305-5537
Property Category	Residential
Property Type	Residential > Single Family > Home
Legal Description	LOT 2 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	2
Jurisdiction	BOULDER CO
Township / Civil Division	BOULDER
Census Block Group	1
Census Block	1018
Census Tract	12507

Owner

170 S 42nd St is owned and occupied by an individual who bought it in June 2026.

Source: Boulder County records, as of September 18, 2026

Owner of Record	Individual Name on File
Mailing Address	170 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.

Deeds, Mortgages & Sale History

Date	Document
Jun 23, 2026	Special Warranty Deed, Transfer · Conventional Mortgage ELEVATIONS CREDIT UNION
Mar 21, 2023	Deed of Trust, Mortgage · Line of Credit AIR ACADEMY FCU

Assessor's Deed Record

Deed Names	Name on Deed
Last Sale	Jun 23, 2026 · Amount on File
Deed Sale	Jun 23, 2026 · Amount on File
Prior Sale	Dec 4, 2009 · Amount on File
Deed Document Number	20264137025
Prior Transfer Date	Apr 29, 1996
Prior Transfer Doc	0001603738
Record Updated	Oct 29, 2026

June 2026: Special Warranty Deed, Transfer

Document Type	Special Warranty Deed
Jurisdiction	BOULDER CO
Recording Date	Jun 23, 2026
Property Address	170 S 42ND ST, BOULDER, CO 80305-5537
Document Number	0004137025
Instrument Date	Jun 17, 2026
Instrument	20264137025
Transaction Type	Transfer
Record Updated	Sep 21, 2026
Title Company	FIDELITY NATIONAL TITLE, FIDELITY NATIONAL TITLE COMPAN

Transaction

Amount	Amount on Record
Downpayment	Downpayment on Record
Loan-to-Value (LTV)	LTV on Record
Tax	$9,847.50
Amount Accuracy	Calculated from Transfer Tax
Additional	Arm's Length

Transferred From (Grantor/Seller)

Name	Verified Name

Transferred To (Grantee/Buyer)

Name	Verified Name
Address	170 S 42ND ST, BOULDER, CO 80305-5537

Mortgage

Document Number	0004137026,
Date	Jun 23, 2026
Instrument	20264137026

Lender

Name	ELEVATIONS CREDIT UNION

Agreement

Type	Conventional Mortgage
Amount	Amount on Record
Term	360 Months
Due	Jul 1, 2056

Interest

Rate Type	Adjustable Rate
Rate	6.5%
Initial Type	Adjustable Rate
Adjustable	Adjustable Rate Rider
Max Rate	-1%

March 2023: Deed of Trust, Mortgage

Document Type	Deed of Trust
Jurisdiction	BOULDER CO
Property Address	170 S 42ND ST, BOULDER, CO 80305-5537
Transaction Type	Mortgage
Record Updated	Mar 28, 2023

Transferred To (Grantee/Buyer)

Name	Verified Name
Address	170 S 42ND ST, BOULDER, CO 80305-5537

Mortgage

Document Number	0004000808
Date	Mar 21, 2023
Instrument	4000808

Lender

Name	AIR ACADEMY FCU
Type	Credit Union
Address	COLORADO SPRINGS, CO 80924

Agreement

Type	Line of Credit
Amount	Amount on Record
Term	239 Months
Due	Feb 15, 2043

Interest

Rate Type	Adjustable Rate
Change Frequency	Monthly

Tax Assessment & Valuation

The 2025 property tax bill for 170 S 42nd St was $5,748.

Source: Boulder County assessment roll, as of September 18, 2026

Property Jurisdictions

Type	Name
State	Colorado
County	Boulder County
Municipality	Boulder City
Unified School District	Boulder Valley School District RE-2 (PK - 12)

Tax Bill & Assessment History

Year	Tax Bill	Assessed Value	Assessed Market Value
2026		$59,908 (+0.79%) Land $32,300 Building $27,608	$951,000 (-) Land $545,000 Building $406,000
2025	$5,748.00	$59,438 Land $34,063 Building $25,375	$951,000 Land $545,000 Building $406,000
2023	$5,648.00 (+11.66%)	$68,227 (+26.51%) Land $39,919 Building $28,308	$1,018,300 (+31.22%) Land $595,800 Building $422,500
2022	$5,058.00	$53,932 Land $29,607 Building $24,325	$776,000 Land $426,000 Building $350,000

Assessed value and assessed market value are set for property tax purposes, not market price estimates; both are a fraction of this property's market value.

Flood

FEMA maps place 170 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	Severe Storms, Flooding, Landslides, And Mudslides, Sep 2013 · 14 claims

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

Wildfire risk around 170 S 42nd St is low, with a 0.03% 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	0.03% annual chance
Exposure	None beyond ember reach

Values cover an area roughly 900 ft across, not the parcel itself; insurers use their own ratings.

Drinking Water

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

Violations Reported to EPA

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.

Internet Providers

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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