Listing provided courtesy of Compass - Boulderas Distributed by MLSGrid- MLS# IR1051395MLS Provider

3621 21st StreetBoulder, CO 80304

Single Family · 4 Beds · 1 Full Bath · 1 Half Bath · 3 Three Quarter Baths · 7,099 Sq. ft. | 0.66 Acres
$12,000,000 Active

3621 21st Street Overview

Time on Site:
138 days
Visits:
2

Meticulously crafted, masterfully built, and expertly curated with an elevated design, this custom home is a true masterpiece, perfectly situated on a premier lot in the exclusive Carolyn Heights neighborhood, The exquisite design and inspiring architecture of this exceptional residence ensures that every facet embodies luxury, casual elegance, and attention to detail, harmoniously blending wood, glass, stone, and steel to create an ambiance that is both inviting and inspiring. Upon entry, you'll be greeted by soaring ceilings, wide plank white oak flooring, & an open-concept main level bathed in abundant natural light streaming through expansive windows, inviting the outside in. The prodigious living area seamlessly integrates indoor & outdoor spaces, offering a glimpse of the splendid living experience that awaits. The architectural grandeur is showcased w/ a dramatic three-story open-tread wooden staircase, custom steel railings, & illuminated by bespoke lighting. The centerpiece of the home, the gourmet kitchen, boasts an impressive center island, marble & quartz countertops, artisanal tile, custom cabinetry, top-tier chef's appliances, & walk-in pantry. The elegant main floor primary bedroom suite is a tranquil retreat, w/ wall-to-wall windows, a generous walk-in closet w/custom cabinetry. The soothing primary bathroom features premium quality finishes, including designer tile, custom cabinetry, & alluring lighting.The heated pool w/ a tanning shelf, natural stone deck, & automatic pool cover takes center stage in the serene yard. Every aspect of this smart home seamlessly integrates technology, design, & automation to ensure security & convenience, and efficiency. For the discerning owner desiring a residence that embodies casual elegance & architectural interest, w/proximity to vibrant downtown Boulder & nestled in an upscale neighborhood, this property is a rare find that offers an unsurpassed lifestyle.

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3621 21st Street Facts & Features

  • Type Single Family
  • Sq. ft. 7,099
  • Price/Sq.ft. $1,690
  • Lot 0.66 Acres

Details

General

Association/HOA

  • Association: false

School Information

  • School District: Boulder Valley RE 2
  • Elementary School: Crest View
  • Middle Or Junior School: Centennial
  • High School: Boulder

Listing Information

  • Concessions: No

Building Information

  • Year Built: 2021

Location/Region

  • Country: US
  • County Or Parish: Boulder
  • Subdivision Name: Carolyn Heights

Tax Information

  • Tax Annual Amount: 55752
  • Tax Year: 2024

General Information

  • Exclusions: Personal Property and Artwork
  • Listing Terms: Cash,Conventional
  • Ownership: Individual
  • Parcel Number: R0004965
  • Possible Use: Residential
  • Property Sub Type: Single Family Residence
  • Property Type: Residential
  • Zoning: RES

Interior

Parking Information

  • Garage Spaces: 3

Beds/Baths

  • Bathrooms Full: 1
  • Bathrooms Half: 1
  • Bathrooms Three Quarter: 3
  • Bathrooms Total: 5
  • Bedrooms Total: 4

Building Interior

  • Above Grade Finished Area: 4544
  • Below Grade Finished Area: 1756
  • Building Area Source: Other
  • Building Area Total: 7099

General Information

  • Appliances: Bar Fridge,Dishwasher,Disposal,Double Oven,Dryer,Freezer,Microwave,Oven,Refrigerator,Trash Compactor,Washer
  • Cooling: Central Air
  • Fireplace Features: Gas,Living Room
  • Flooring: Tile,Wood
  • Heating: Radiant
  • Interior Features: Eat-in Kitchen,Five Piece Bath,Kitchen Island,Open Floorplan,Pantry,Vaulted Ceiling(s),Walk-In Closet(s),Wet Bar
  • Laundry Features: In Unit
  • Levels: Two
  • Living Area: 6300
  • Main Level Bathrooms: 2
  • Main Level Bedrooms: 1
  • Security Features: Fire Sprinkler System,Smoke Detector(s)
  • Window Features: Double Pane Windows,Window Coverings

Exterior

Parking Information

  • Parking Features: Heated Garage,Oversized
  • Parking Total: 3

Lot Information

  • Lot Features: Level,Sprinklers In Front
  • Lot Size Acres: 0.66
  • Lot Size Square Feet: 28700
  • Road Surface Type: Paved
  • Vegetation: Grassed,Wooded
  • Water Source: Public

Building Exterior/Construction

  • Architectural Style: Contemporary
  • Attached Garage: true
  • Construction Materials: Block,Brick,Stone,Frame
  • Direction Faces: East
  • Patio And Porch Features: Patio
  • Roof: Composition
  • Structure Type: House

General Information

  • Exterior Features: Dog Run,Gas Grill,Spa/Hot Tub
  • Pool Features: Private
  • Road Frontage Type: Public
  • Sewer: Public Sewer
  • Utilities: Cable Available,Electricity Available,Internet Access (Wired),Natural Gas Available

Room Information

Room: Bathroom Three Quarter

  • Level: Lower

Room: Bedroom

  • Level: Lower
  • Length: 16
  • Width: 16
  • Description: Carpet

Room: Game Room

  • Level: Lower
  • Length: 20
  • Width: 20
  • Description: Wood

Room: Bathroom Full

  • Level: Main
  • Features: Primary Suite

Room: Bathroom Half

  • Level: Main

Room: Bedroom

  • Level: Main
  • Length: 17
  • Width: 17
  • Description: Wood
  • Features: Primary Suite

Room: Dining Room

  • Level: Main
  • Description: Wood

Room: Kitchen

  • Level: Main
  • Length: 14
  • Width: 25
  • Description: Hardwood

Room: Laundry

  • Level: Main
  • Length: 11
  • Width: 9
  • Description: Tile

Room: Living Room

  • Level: Main
  • Length: 26
  • Width: 31
  • Description: Wood

Room: Office

  • Level: Main
  • Length: 17
  • Width: 16
  • Description: Wood

Room: Bathroom Three Quarter

  • Level: Upper

Room: Bathroom Three Quarter

  • Level: Upper

Room: Bedroom

  • Level: Upper
  • Length: 15
  • Width: 16
  • Description: Carpet

Room: Bedroom

  • Level: Upper
  • Length: 12
  • Width: 17
  • Description: Carpet

3621 21st Street Neighborhood

Community

80304 (Boulder) Demographics

41
Median Age
2,891
Population Density (per sq. mile)
81%
College Educated
$98,049
Estimated Median Income
7,931
Estimated Total Home Owners
3,417
Estimated Total Renters
70% / 30%
Estimated Owner / Renter Divide
2
Estimated Average Household Size
Community data courtesy of LiveBy, Inc.

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.

3621 21st Street Monthly Cost

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* All calculations are estimates and provided by Reliance Network, for informational purposes only. Actual amounts may vary. ** Assumes 6.50% APR, 20% down payment, and conventional 30-year fixed rate first mortgage. Rates cited are for instructional purposes only; current rates are subject to change at any time without notice. You should not make any decisions based simply on the information provided. Additional required amounts such as taxes, insurance, homeowner association dues, assessments, mortgage insurance premiums, flood insurance or other such required payments should also be considered. Contact your mortgage company for current rates and additional information. Any mortgage broker or insurance agent that may appear is independent and is not affiliated with, endorsed by, or provided by the MLS.

3621 21st Street Market Data

Based on the last 30 days in this zip code

$2,503,375
Average List Price
$799
Average Price per Square Foot
46
Properties Sold
101
Average Days on Market
233
Properties for Sale
Calculations provided by Reliance Network

3621 21st Street History

Date Event Value Agent
6/4/2026Source: REColorado MLS Status Change
Active
5/22/2026Source: REColorado MLS Status Change
Pending
2/27/2026Source: REColorado MLS Price Reduction
$12,000,000 -7.7%
2/27/2026Source: REColorado MLS Status Change
Active
2/21/2026Source: REColorado MLS Status Change
Pending
2/11/2026Source: REColorado MLS Added to Database
February 11, 2026