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Boulder, CO 80304 3633 21st St

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  • MLS# 1051043
  • 02/06/2026
  • Request Tour
  • Request Info
  • Beds • 7
  • Full/Half Baths • 4 / 1
  • Garage • 3

Home Details

Exquisite secluded sanctuary in the heart of Carolyn Heights. Tucked into one of Boulder's most prestigious enclaves, this estate offers a rare fusion of luxury, privacy, and relaxed sophistication. Set on a serene, tree-lined .81-acre level lot, this 7-bedroom, 5-bathroom oasis is where inspired design meets effortless living. Stunning views of the Flatirons awaken you each morning from your bed. Those same views tease your senses from the expansive patios with fully retractable doors that blur the lines from inside to outside. Bathed in natural light from soaring windows and skylights, every detail has been thoughtfully curated. Custom walnut doors and paneling welcome you into the home and invite you to explore. The chef's kitchen is a showstopper-featuring custom cabinetry, an oversized marble island, and top-of-the-line Thermador appliances. The open-concept layout flows seamlessly into a lush backyard oasis, perfect for gatherings or quiet moments of retreat by the fire pit. The primary suite is a haven unto itself with vaulted ceilings, a spa-inspired bath, spacious walk-in closet, and private deck access. With multiple flexible living spaces-including a dedicated home office and media room, this home is ready to adapt to your every need. Located minutes from North Boulder's best hiking trails, cycling routes, farmers markets, and local eateries-yet nestled in the peaceful privacy of a mature, sought-after neighborhood. Elevated living starts here. LIVE BOULDER, LOVE BOULDER!
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Interior Features for 3633 21st St

Bedrooms

Total Bedrooms7

Bathrooms

3/4 Baths1
Half Baths1
Total Baths5

Other Interior Features

LivingAreaSourceAssessor
Above Grade Finished Area4798
BasementFull, Daylight
Below Grade Finished Area2190
Fireplace FeaturesGas
FlooringWood
Interior AmenitiesEat-in Kitchen, Separate Dining Room, Cathedral Ceiling(s), Open Floorplan, Pantry, Wood Windows, Walk-In Closet(s), Skylights, Kitchen Island
Window FeaturesSkylight(s)

Other Rooms

Room TypeMedia Room

General for 3633 21st St

AccessibilityLevel Lot, Level Drive, Low Carpet
AppliancesGas Range, Dishwasher, Refrigerator, Washer, Dryer, Microwave, Disposal, Fire Alarm
Architectural StyleContemporary
AttributionContact7203941997
CityBoulder
Construction MaterialsFrame
CoolingWall/Window Unit(s), Ceiling Fan(s)
CountyBoulder
DisclosuresSeller's Property Disclosure
ElectricXCEL
Elementary SchoolColumbine
ExclusionsSellers personal property and any staging items
Expected Active Date 2026-02-06
Full Baths3
Garage Spaces3
HOANo
HeatingHot Water, Zoned, Radiant
High SchoolBoulder
High School DistrictBoulder Valley Dist RE2
LevelsTri-Level
Living Area6988
MLS AreaBoulder
Middle/Junior High SchoolCentennial
New ConstructionYes
Parcel NumberR0004105
Patio/Porch FeaturesPatio, Deck
Possible UseSingle Family
Property Attached Y/NNo
Property SubtypeSingle Family Residence
Property TypeResidential
RoofComposition
Security FeaturesFire Sprinkler System
SewerPublic Sewer
Standard StatusActive
StatusActive
Subdivision Name21st/Linden Sub
Tax Annual Amount29641
Tax Year2025
UtilitiesNatural Gas Available, Electricity Available
ViewHills
Virtual TourClick here
Year Built2024
ZoningRES

Exterior for 3633 21st St

Exterior AmenitiesSprinkler System, Oversized Garage
FencingPartial, Security
Irrigation Water Rights Y/NNo
Lot FeaturesWooded, Evergreen Trees, Deciduous Trees, Level, House Faces South
Lot Size Acres0.81
Lot Size Area35311
Parking FeaturesAttached
Water SourceCity
Waterfront Y/NNo

Additional Details

Price History

Schools

Elementary School Columbine Elementary School
High School Boulder High School
Middle School Centennial Middle School

Nathan Washam

Broker/Owner
Price $10,000,000
MLS#1051043
List Date 02/06/2026
Property Type Single Family
Phone 970.988.8295
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