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303 WINDOWS

Denver Window Installers
Ranked #1 in Denver | Grade A+
5.00 (262 reviews)

303 WINDOWS

303 WINDOWS focuses on replacement windows for Denver homes, providing clear estimates, dependable scheduling, and careful installation practices.

Why Homeowners Choose This Business

Local knowledge of Denver homes, attentive measuring and fit, and a straightforward estimate process make 303 WINDOWS a practical choice for replacement projects. Strong recent customer feedback highlights communication, punctuality, and clean job sites.

Service Area

Serving Denver and nearby metro communities from the location on S Downing St; service radius depends on project details and availability.


How This Business Compares

A quick local comparison based on ranking, review strength, and market visibility.
  • Ranks among the top local businesses in this market.
  • Performs at or above the local average for Google rating.
  • Shows strong customer satisfaction signals based on review quality and volume.

Services Covered

  Renovation Services
  Service
  Installations
  window replacement
  window installation
  vinyl windows
  energy efficient windows
  Casement windows
  double hung windows
  sliding windows
  picture windows
  Custom Sized Windows
  Colorado window contractor
  residential windows
  window trim and casing

Services include in-home assessments, window replacement, new window installation for remodels, custom sizing, trim and casing updates, and removal and disposal of old units. Typical projects involve vinyl and other common residential window materials, with options suited to Denver’s climate and altitude.


Recent Reviews

5.00

(Based on 262 reviews)

Recent online reviews show consistently high marks for responsiveness, fair pricing discussions, and careful installation, with many customers noting smooth scheduling and respectful crews.

Google Review
Lea C on 303 WINDOWS

Our recent experience with 303 Windows was exceptional! The team was a true pleasure to work with. Jay provided a thorough, fair, and quick proposal. After consideration, we decided to move forward with window replacements in only our kitchen instead of the entire home. When we relayed this to Jay, we never felt any pressure for the reduced scope and he quickly scheduled us. The installation team of Jake, Max, and Chuy was outstanding - they were engaging, professional, respectful of our home, and went far beyond our expectations. The finished picture windows are stunning! They are beautiful, high quality, and allow us to fully enjoy the beauty of our backyard. I cannot recommend this team enough!

Google Review
Patrick Schmidt on 303 WINDOWS

Our experience with 303 Windows was excellent from start to finish. We needed to replace a very old and large front window, and the entire process was seamless.

Our initial meeting with Jay was great. He was straightforward, honest in his assessment, and a pleasure to speak with. He provided us with an estimate on the same day, which made our decision easy when considering other vendors.

As for the installation, we could not be happier with the professionalism and skill displayed by Jake and his crew. Our new front window looks absolutely beautiful, and we especially love the custom trim work they did.

We plan on replacing other windows in our house, and there is no doubt that we will be working with 303 Windows for those future projects.

Google Review
Jessica on 303 WINDOWS

Outstanding Local Window Company – Exceptional Value and Quality Work!

We couldn’t be happier with our experience. From start to finish, 303 windows delivered top-notch service, incredible value, and workmanship that truly exceeded our expectations. Our first meeting with Jay was so straight forward and efficient. He had the house measured in 30 minutes where other big name companies took as much as 3 hours. He got us a quote that same day.

The team of Jake, Max, Chuy, Alan, Faris, and Marquise were extremely professional, punctual, and clearly skilled at what they do. By the end the whole group felt like family. The installation was smooth, efficient, and done with great attention to detail. Our new windows look fantastic and have already made a noticeable difference in the comfort and appearance of our home. On top of that, their pricing was extremely fair—especially considering the high quality of the products and the level of care they put into the job.

If you’re looking for a local family owned company that combines great value, excellent craftsmanship, and an stress-free experience, look no further. Recommended with no reservations whatsoever.

Google Review
Saskia Sawyer on 303 WINDOWS

We had nine windows replaced by 303 windows and the crew (Jake/Max/Chuy/Alan/Faris) was simply great. Communication was great from the start, everything and everyone was on time and the workmanship exceeded our expectations (especially as they had to address quite a few issues with the old frames). The guys, courteous and respectful, clearly enjoy their craft.
We cannot say enough good things about our experience with 303 Windows and we highly recommend them for any size job.

Google Review
Kelly Dahmer on 303 WINDOWS

Love our new windows! We had very old windows (original from 1888) that needed to be replaced. Really love the new windows. They brighten the space and make the room look larger. The guys were very professional and kind. Install was very easy. I am very particular and they made sure I was happy with the final product even doing some drywall work since I was wanting a minimal look (no trim). Really appreciate the customer service and attention to detail. Thank you! Posting before and afters…


Special Offers

Free Estimate

This business may offer free estimates for some services.


Frequently Asked Questions

Most residential window styles are supported, including double-hung, sliders, casement, picture, and specialty sizes. Material options commonly include vinyl and other standard residential choices suited to Denver’s climate.

A visit is scheduled to review goals, measure openings, and discuss options. You’ll receive a written estimate outlining products, scope, and timelines so you can make a clear decision.

After ordering, lead times vary by product and season. Installation for an average home is usually completed in one to two days, with scheduling confirmed in advance.

Yes, removal and disposal of old units are typically included in the scope. The crew also aims to protect interior spaces and clean up the work area before completion.

Yes, the team can discuss energy-efficient glass packages and frames that perform well at altitude and in varying temperatures. Product recommendations are tailored to your home’s orientation and goals.
 Verified Listing

Opening Hours


  • Monday 7:00 AM – 9:00 PM
  • Tuesday 7:00 AM – 9:00 PM
  • Wednesday 7:00 AM – 9:00 PM
  • Thursday 7:00 AM – 9:00 PM
  • Friday 7:00 AM – 9:00 PM
  • Saturday 7:00 AM – 9:00 PM
  • Sunday 7:00 AM – 9:00 PM

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Business Details


Business Rating
5.00 (262 reviews) FeaturedPro Business
Address
2375 S Downing St, Denver, CO 80210, USA, Denver, CO 80210, US
Business Type
general_contractor

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