


3421 4th StreetBoulder, CO 80304
Single Family · 6 Beds · 2 Full Baths · 1 Half Bath · 2 Three Quarter Baths · 5,198 Sq. ft. | 0.60 Acres3421 4th Street Overview
- Time on Site:
- 108 days
- Visits:
- 1
Newlands Sanctuary on Mt. Sanitas Open Space Step onto the 600-square-foot deck and look up. Mt. Sanitas rises 1,300 feet from your backyard gate, private access to the Goat Trail. No driving. No parking. Just you, your coffee, and maybe a 4-legged friend who will make sure you don't skip it. This premier property is one of eight homes backing directly to open space. In 21 years, only one has changed hands. Hidden behind a 70-yard tree-lined driveway on a 0.6-acre lot (2.5x standard), this is widely regarded as one of Boulder's best addresses, served by top rated schools.The 5,200-square-foot residence features 20-foot ceilings with west-facing glass framing Mt. Sanitas, white oak floors, two fireplaces, and a library overlooking the property's seven heritage apple trees. Six bedrooms plus office (convertible seventh) include three distinct suites: the primary en-suite with a stunning view; a garden-level walkout in-law addition (2005, 12' ceilings) with separate entrance, private patio, and dedicated office-ideal for multigenerational living or guests-plus a basement suite with whirlpool bath. Outside you will discover a deep wrap-around porch beneath a 60-foot silver maple, flower and vegetable gardens, and the historic Silver Lake Ditch with 12,000 gallons daily water rights. Sundance Film Festival arrives January 2027, venues minutes away providing a chance at an incredible rental income opportunity and under the Augusta Rule, 14 days of rental income may be tax-free. Roof replaced 2019. New carpet. Heated two-car garage. No HOA. No covenants. For those who know Newlands: this is the privacy, the lot, the view, and the trail access that almost never comes to market. For those discovering Boulder for the first time: welcome to the neighborhood the locals covet most.
3421 4th Street Facts & Features
- Type Single Family
- Sq. ft. 5,198
- Price/Sq.ft. $1,308
- Lot 0.60 Acres
Details
General
Association/HOA
- Association: false
School Information
- School District: Boulder Valley RE 2
- Elementary School: Foothill
- Middle Or Junior School: Centennial
- High School: Boulder
Listing Information
- Concessions: No
Building Information
- Year Built: 1990
Location/Region
- Country: US
- County Or Parish: Boulder
- Subdivision Name: Fourth Street 3403 Sub
Tax Information
- Tax Annual Amount: 26030
- Tax Year: 2025
General Information
- Exclusions: Furnishings and Personal Property, Water Rights Included
- Listing Terms: 1031 Exchange,Cash,Conventional
- Parcel Number: R0108936
- Possible Use: Residential
- Property Sub Type: Single Family Residence
- Property Type: Residential
- Zoning: SFR
Interior
Parking Information
- Garage Spaces: 2
Beds/Baths
- Bathrooms Full: 2
- Bathrooms Half: 1
- Bathrooms Three Quarter: 2
- Bathrooms Total: 5
- Bedrooms Total: 6
Building Interior
- Above Grade Finished Area: 3927
- Below Grade Finished Area: 1095
- Building Area Source: Other
- Building Area Total: 5198
General Information
- Appliances: Dishwasher,Disposal,Down Draft,Microwave,Oven,Refrigerator,Self Cleaning Oven
- Cooling: Ceiling Fan(s),Evaporative Cooling
- Fireplace Features: Family Room,Gas,Gas Log,Living Room
- Heating: Forced Air,Hot Water,Radiant
- Interior Features: Eat-in Kitchen,Five Piece Bath,Open Floorplan,Vaulted Ceiling(s),Walk-In Closet(s)
- Levels: Three Or More
- Living Area: 5022
- Main Level Bathrooms: 2
- Main Level Bedrooms: 1
- Security Features: Smoke Detector(s)
- Spa Features: Bath
Exterior
Parking Information
- Parking Features: Oversized
- Parking Total: 2
Lot Information
- Lot Features: Ditch,Open Space,Rolling Slope,Sprinklers In Front
- Lot Size Acres: 0.6
- Lot Size Square Feet: 26072
- Road Surface Type: Paved
- Vegetation: Wooded
- Water Source: Public
Waterfront/View
- View: Mountain(s)
Building Exterior/Construction
- Architectural Style: Contemporary
- Attached Garage: true
- Construction Materials: Frame,Wood Siding
- Direction Faces: East
- Patio And Porch Features: Deck,Patio
- Roof: Composition
- Structure Type: House
General Information
- Fencing: Fenced,Partial
- Road Frontage Type: Public
- Sewer: Public Sewer
- Utilities: Cable Available,Electricity Available,Internet Access (Wired),Natural Gas Available
Room Information
Room: Bathroom Full
- Level: Basement
Room: Bedroom
- Level: Lower
- Length: 15
- Width: 13
- Description: Carpet
Room: Game Room
- Level: Lower
- Length: 14
- Width: 18
- Description: Other
Room: Laundry
- Level: Lower
- Length: 10
- Width: 6
- Description: Other
Room: Bathroom Half
- Level: Main
Room: Bathroom Three Quarter
- Level: Main
Room: Bedroom
- Level: Main
- Length: 17
- Width: 23
- Description: Wood
Room: Dining Room
- Level: Main
- Length: 12
- Width: 13
- Description: Wood
Room: Great Room
- Level: Main
- Length: 14
- Width: 19
- Description: Carpet
Room: Kitchen
- Level: Main
- Length: 10
- Width: 15
- Description: Wood
Room: Living Room
- Level: Main
- Length: 13
- Width: 15
- Description: Wood
Room: Office
- Level: Main
- Length: 11
- Width: 12
- Description: Wood
Room: Bathroom Full
- Level: Upper
- Features: Primary Suite
Room: Bathroom Three Quarter
- Level: Upper
Room: Bedroom
- Level: Upper
- Length: 11
- Width: 13
- Description: Carpet
Room: Bedroom
- Level: Upper
- Length: 15
- Width: 17
- Description: Carpet
- Features: Primary Suite
Room: Bedroom
- Level: Upper
- Length: 12
- Width: 12
- Description: Carpet
Room: Bedroom
- Level: Upper
- Length: 11
- Width: 15
- Description: Carpet
3421 4th Street Neighborhood
Community
80304 (Boulder) Demographics
Schools
School data courtesy of LiveBy, Inc. School ratings are based on a scale of 1-5, with 5 being the highest rating and 1 being the lowest rating.3421 4th Street Monthly Cost
3421 4th Street Market Data
Based on the last 30 days in this zip code
3421 4th Street History
| Date | Value | Agent |
|---|---|---|
| 3/13/2026Source: REColorado MLS | March 13, 2026 |













































