Don't hesitate, call now!  Over the past seven years we replaced all of our windows.  We did this in thirds:  The first and second time we went through Discount Windows and Siding.  This is when they were discount windows.  Since then their prices tripled which prompted us to shop around, obtaining estimates from four more window companies.  Enter Jay from 303 Windows.  What a breath of fresh air!  From the first call Jay was prompt, professional, courteous, VERY KNOWLEDGEABLE, reasonable, observant, and keen on details (he was the only window man in seven years who pointed out that the grids in our windows did not match the others).  He's a straight shooter who won't steer you in the wrong direction.  Any follow-up questions or concerns are immediately addressed and resolved.  Others may have had lower bids, but Jay's integrity and confidence won the day.    From start to finish, the measuring, estimating, ordering and installation went without one hiccup.  I'd like to talk more about the people (very good communicators and listeners) before I describe the windows.  Rick came out to do the measuring.  He was fast and efficient.  Five guys showed up on installation day:  John, the front man who had the sweetest disposition, explained what they were going to do and how they would do it.  Dan, the most energetic and spry person I've met to date, elected to be the one to install the window over my jetted tub because he was the lightest of the men and wanted to place the least amount of pressure standing on it.  Let me clarify that most of the work was done from the outside on all windows.  Upon meeting Vincent he quipped, "Nice to meet you".  I can't tell you the last time a young man has said that to me.  Two other men showed up as I was leaving for work do I did not get their names.  These five professional, hardworking and very competent men installed 9 windows in 4 hours.  As with any project, touch-ups were needed.  Both John and Dan asked me for my touch-up paint so they could leave my walls as they found them.  I was totally impressed with their caulk lines by the way.   The windows:  We hesitated 2 weeks putting our blinds back up because the windows are so darn pretty to look at.  Functional?  Hell yes and way better than the Discount Windows we currently have and those we've seen from other companies.  303 Windows have more sophisticated features such as an aluminum bar running the length of the window to remove the screen (instead of cheap plastic tabs that break), clean lines, curved locks that your fingers can easily manipulate, and an overall design that makes the windows look elegant.  They are both lightweight and durable, open and close without throwing your back out, secure, and help reduce noise.  In addition, all parts can be replaced such as latches, locks and security features vs replacing the entire window.   Since starting this journey seven years ago, we've had a great deal of estimates and salesmen at our house including Andersen, Champion, Home Depot, Lowes, Southwest, Affordable, and Gravina's along with other companies and contractors we have long since forgotten.  Oh the stories we could tell!  Save yourself the time and frustration.  Call 303 Windows now!  I wish we would have seven years ago! read more

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Jay handled replacement of all our old windows and new windows and doors for our renovation project. The windows came when promised and installed by his expert team. Jay, is also very honest. He came to look at the installation and realized that one of our window was the wrong color. He immediately let us know and ordered a new one. I would highly recommend Jay and his team to do you window and door project. read more

I almost never leave reviews, but 303 Windows did a fantastic job replacing our 14 townhome windows. Rich was efficient, professional, and went the extra mile to make sure we were happy with the final installed product. Excellent service and terrific value! read more

Update 09-16-2024 One of our windows wasn't sliding as well as we would like. I contacted Jay and he immediately placed a service order with Anlin who called us to set up an appointment. Less than two weeks later, Carlos with Anlin stopped by and promptly took care of the problem. Very happy! read more

I don't usually write reviews, but 303 Windows has earned it. I was on a mission to get my whole house re-windowed and add a slider to my dining room at the same time. I decided to go with 303 Windows mostly because I felt taken care of from the start. Jay was way more interested in getting the right replacement windows for our 1956 brick home than others that bid the job. He was the only contractor to recommend we replace our original casement style windows with new egress casements. The rooms now feel bigger because the windows are larger single pieces of glass that open to a 90 degree angle instead of two smaller pieces of glass split by a steel post that hardly open at all. I have zero regrets when comparing them to conventional sliding windows. We also had 303 Windows convert a nonfunctional dining room window into a sliding glass door. They even did the brick work! It has changed how we move around our house drastically and our dog loves it. Two of our window screens arrived damaged and Adrian, the crew chief, told me about that on install day and that he'd have to get them ordered. When Jay came by to check on the job after completion I mentioned it to him as well. Remember I told you I felt taken care of? Jay called his account manager at Anlin while he was standing in my living room to make sure those screens got replaced. He kept his word and they were installed a week later. Both of Jay's sons and also Adrian's son were on my install crew. Kind of feels like the old days of family run businesses passed down generationally. It is refreshing to work with a company that is looking to be around a while. read more

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I cannot say enough great things about Jay and his team! Jay originally was one of three companies to come to my business to give an estimate. I had three specific requests. I wanted both security windows as well as black frames on the inside and out. Despite that the brand of windows he sells are generally white on the inside, Jay enlisted a painter to paint the interior frames black. He also delivered on a unique request to have a pine wood ledge installed with pine wood frames. Lastly, it was communicated up front that I was looking to work with unambiguously SOBER staff. If you have worked with contractors of late, you'll know there is many spacey ganja smokers and tweaky meth heads. All staff were sober and alert. In 2023 that is a competitive advantage! Now our stained glass art and hanging plants are framed in warm wood, as demonstrated in the photos below. read more

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We actually had Jay come out a few years ago and give us a quote on all our windows. As things happen we put it on hold! Finally, this year we redid our kitchen, replaced 4 new front windows, new slider and new kitchen window. All windows arrived on time, and look great. His son Jake came back out and replaced a handel we wanted changed to a lock. Very nice and easy to work with. We'll be ready next year to replace the rest of our UGH 1969 windows. read more

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What a great experience! We had multiple quotes for an entire house window replacement project but it was Jay and his presentation, products, pricing, and reviews that made us choose 303 Windows. When it came time for the install, we had the pleasure of meeting Jake, Max, and Chuy as our installation team. This team was incredible! They were the hardest working craftsmen we've ever met! They were talented, knowledgeable, efficient, detail oriented, and protective of our home. They worked very hard for 2 long days to make sure our job was completed on time. We very strongly recommend this business for your windows project! read more

I couldn't be happier with the work done by 303 Windows. We had originally contacted a larger retailer who quoted us thousands more, and we were going to have to make sacrifices in terms of style. I'm so glad I contacted 303 Windows. We got custom windows for way less. Jay was always so responsive and professional. And the installers were on time, did a great job, and were in and out in no time! If you need windows in the Denver area, do yourself a favor and contact Jay with 303 Windows. You won't be disappointed! :) read more

303 Windows - Picture windows in front of house - Windows Installation Near Me - Denver, Colorado

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There have been issues but Jay, the owner, is working to get those corrected. Will write a more comprehensive review once everything is complete. read more

Jay provided a fair quote and was easy to work with. I appreciate the crews job to get the windows installed in just a few days. The windows are far better than the original single pane. read more

303 Windows - New windows - Windows Installation Near Me - Denver, Colorado

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I highly recommend 303 Windows and owner Jay Lillien. In early 2021, We had Jay and his team at 303 windows replace all windows in our home in Littleton with Amerimax replacement windows (manufactured in Loveland). We are very pleased with the results. We are exceptionally pleased with the professionalism, friendliness, responsiveness and workmanship of the crew, who swapped out all 27 or so windows over two days, and cleaned up all debris. We had a couple minor problems with the windows (a long narrow eyebrow window cracked during a difficult installation, and a few windows had minor manufacturing defects- small bits of bitumen sealant between the panes of glass).., but all problems were fixed promptly and efficiently at no cost to us through 303Windows workmanship guarantee and Amerimax's double lifetime warranty (you can pass it on to the next owner of your house). When looking at replacement windows, there are a lot of options out there and I did a fair amount of research before deciding. I wanted to use an independent local shop, rather than one tied to a manufacturer, and also use windows manufactured locally. In my research, I learned that if there is a significant difference in elevation (more than 5000') between the factory and the installation location, the likelihood of seal failure in double pane windows increases. My runner up window choice is made in California, and would have had to be shipped up over the passes, as well as being installed at an elevation more than 5000' above the factory. The Loveland-made Amerimax windows, made with high-quality Cardinal glass, look great, are solidly constructed, and have clean lines and sturdy screens. They significantly quiet the house compared to the 1996-era original windows, and keep the house warmer in winter and cooler in summer. Jay, the owner of 303Windows is a delight to work with and brings decades of experience and dedicated work crews. He noticed how the horizontal center bar of the windows in the front of the house were not aligned with the windows in the back of the house and suggested a 60/40 split in the front windows to line them up with the back. A small detail, but they look great inside and out. He made several other very helpful suggestions and was very responsive to any questions I had. After the installation, I recommended 303Windows to a couple of my neighbors who also decided to have 303 replace their windows. They too are very happy with the results. read more

303 Windows - Windows Installation Near Me - Denver, Colorado

Jay and the crew did an amazing job with our windows. The whole process was easy and the price was great. I can't recommend them enough

My wife and I went through 303-WINDOWS after seeing the prices of many of the "Name Brand" companies. We were quoted 25k-30k for 21 windows by these companies. When Jay came out, he explained everything to us and was non invasive. He quoted us at 12k for 21 windows! I was a little concerned about the quality at first, but after talking to a couple other people, those concerns were abated. The windows were installed in 1 day. The crew that installed them was respectful and fast. I couldn't have been happier with the service I received and the windows are ABSOLUTELY WONDERFUL! The warranty is unbelievable! A mouse chewed through my screen on my basement window, after a 5 minute phone call, Jay had a free replacement on order for me. I would recommend anyone looking at this review to stop wasting their time looking and simply go with 303-WINDOWS. Thank you again to all the staff at 303-WINDOWS. read more

I had all the windows replaced in my house and John and Max were amazing. They were on time, polite, friendly, and clean! They went above and beyond. Big thanks to Jay and the whole team for upgrading my house! read more

I had 303 Windows install all new window & doors on my home 3 years ago. I was recently having an issue with my patio door lock not working. I made one call to 303 Windows and within 24 hours they had a tech out to repair my door lock. I've been selling Real Estate for over 20 years and this is by far some of the best customer service you will find from a window and door contractor. If you are thinking of getting windows calling 303 Windows is a must. Not only will you get excellent windows, great installers but awesome customer service. read more

The top 10 reasons why I LOVE 303 Windows 1. Jay: He is reliable as well as very knowledgeable. 2. Love my windows! Much more energy efficient than I ever imagined! 3. Fair price! 4. Great installers: They were on time, cleaned up after themselves, and very hardworking. 5. Jay kept me informed through every step of the process. 6. Everyone was wonderfully professional. 7. Accurate measurement. 8. One of the window panes needed to be replaced, Jay was on it right away. 9. Jay assisted with the design of the windows. 10. I LOVE MY WINDOWS. I only wish I had replaced them sooner. read more

We researched numerous window replacement providers, and after meeting with Jay (the owner), we knew 303 Windows was the right fit for us. They were affordable, professional, and installed a great product. Jay's recommendations and advice ensured that we knew what to expect and were 100% happy with the final result. Thank you, 303 Windows, for helping to make our home beautiful! We highly recommend 303 Windows. read more

My experience with Jay, the owner, was fantastic from the minute I talked to him on the phone. He was on time, professional and listened to want we wanted to do with our windows. He had several windows and took the time to explain the differences between the windows. No pressure. It was an easy choice to have Jay install the new windows. When the windows arrived, he called and set up a time for installation. His crew was very professional, answered my questions and took the time to make sure the work area was spotless before they left. The new windows look fantastic! If you need new windows, don't waste your time calling anyone else. read more

My windows are being installed today and they look beautiful! Rick is so clean, organized, friendly and doesn't mind that my dogs keep barking at him, lol. But seriously Jay was great when he quoted me, kept to his price and honestly does business. Very reasonable pricing and no hidden fees. Had 8 windows replaced and would like to replace some picture windows in time. I will most definitely call Jay and Rick again! read more

Went with 303 windows because they were highly recommended and had great reviews. Maybe it was an off week for Jay, but we didn't have a great experience. Communication was poor about when the installers would arrive. I have kids and dogs and needed to have a window of time, but the installers' arrival was hours off Jay's estimate. Jay subs out the installation and that is really who you need to be good. We had one cracked window frame that the installers installed anyway. Jay replaced it, but we had to wait several weeks. In addition, unfortunately the installers also broke one of yard lights during installation. Jay completely ignored our request to replace it. He also promised repair parts for an existing kitchen window. He never supplied the parts. His son was working with the installer and did the window caulking. He smeared caulk all over the side of our house when caulking an upper window. Caulk also dropped down from the second floor window to the ground windows. Just very sloppy. Price was ok, but installation quality isn't there. Would not recommend. I'm only reviewing because not sure how they have all 5 star reviews and no one says anything negative. Just be aware you may not have the 5-star experience. read more

I'm a home owner in the Denver metro area and shopped around when looking for replacement windows but was totally turned off by the selling techniques of all the window companies. My house is pretty old and had metal framed windows, single pane with bid metal framing on the inside. I knew it wasn't going to be an easy window project and trust me, the other companies I entertained made it sound like a huge cost factor to change this out. When I reached out to Jay at 303 Windows it was like a breath of fresh air. They were very familiar with the type of house and windows, answered all my questions, wasn't pushy or trying to sell me anything other than the windows. These guys are straight shooters and just down to earth good people. When it came time for the windows to be installed, the crew was prompt, courteous and very professional. John and his team did an outstanding job where all the windows looked great, adding all new trim and molding, inside and out. Super happy with the window quality but especially with the installation. I would highly recommend this company to anyone looking for replacement windows. They rock! read more

We have a 70 year old house with original windows. Once my husband and I were finally able to afford replacing the windows, we got quotes from about 10 companies around Denver. By far, the most knowledgable and one of the best priced happens to be 303-Windows! Our custom windows were ready in about 6 weeks. We scheduled a perfect February day and within about 5 hours, our windows were installed! The installers were prompt, professional, hilarious, and kind. They cleaned the entire work area, before and after and made sure the windows were sparkling when they left. I never expected to be so happy to spend so much money. These brand new windows are glorious! read more

Recently received quotes and replacement windows from 303-windows. Jay offered options and advice that were very helpful and made the difference on our choice. John and his installation crew were respectful and thorough. They were on-time, proficient and even repaired a damaged window casing. We appreciated their honesty, expertise and professionalism. We are enjoying our new windows, blocking out more sound and energy efficient. Thank you Jay, John and crew! read more

If you are looking for a window company that provides quality product, excellent customer service and expert installation, highly recommend 303 Windows. The owner of the company, Jay, is extremely knowledgeable and responsive. Also, the installers are timely, professional and pleasant. We absolutely love our windows. read more

We were extremely happy with 303 Windows. We recently had four windows in the front of our house replaced in addition to an architecture window in our living room. We were impressed with both Jay and Rick and would highly recommend this business. read more

In today's society, it's hard to find honest, respectful, hardworking individuals that take pride in their work and offer a great customer experience. Before I called 303-WINDOWS, I was very skeptical thinking this would be another "buyer beware" sort of experience full of surprises and unpleasntries. It never fails, whenever I need something done to my home, car, etc., honesty and integrity seems to take a back seat with whoever I hire. Within minutes of talking to Jay (the owner), he put me at ease and was very pleasant to talk with on the phone. I needed an estimate and he got me in the next day which was great as it was a Saturday and I did not have to take time off from work. Upon arrival, Jay brought the sample tan colored windows I had requested as I was unsure about the tan color. Jay is a great guy and easy to talk to. He has a tremendous amount of knowledge on windows and construction in general. He's also DU graduate which speaks volumes. Jay offered advice on windows where needed. For example, he noticed one of my bedroom windows upstairs had the slider located where it would be unsafe to escape using the window. He recommended I have the slider located on opposite side for safe exit in the event of a fire. Not only did he have safety in mind but he had other suggestions which we implemented as well. As far as the price, Jay's bid came in lower than the competition even with dissimilar sound deadening glass for all 24 windows and the addition of a third window in a bedroom. You will not be disappointed in Jay's pricing. Do yourself a favor and have Jay a give you a quote. Regarding the installation, I could not have had a better experience. All 24 windows and the custom window work were completed in just 2 days! Jay's crew of 4 were simply awesome! They were polite, personable, clean, and meticulous about their work. It was breath of fresh air to see people who actually take pride in their work and respect others property, something that is very hard to come by these days. They were very careful not to damage, scrape, or scuff any walls, railings, floors, etc when they did the install. Jay and his crew also installed a 3rd window in a bedroom for me and replaced the existing 2 windows with larger windows. So, not only do they offer window replacement, they can do custom work as well which worked out great! I can honestly say, this was the best in home service experience I have ever had, hands down. One last very important thing, if something is not right, you can count on Jay to make it right. He wants you, as a customer, 100% satisfied with his work. I experienced this firsthand. The drywall texture was not quite right in the room where the custom work was done. Before I even had a chance to call Jay about this, he actually called me about it and said he was going to have a professional drywaller come over and fix the texturing!!!! Talk about a great team of workers...one of his crew noticed the texture was not right, he told Jay about this, and Jay called me and had a professional come over and correct the texture! It simply does not get any better than this! I was blown away with the great service. Regarding the windows, I went with the Amerimax Craftsman Series with dissimilar glass (for sound deadening) and went with the tan color. I would say they are at least 50% quieter. On a sunny day, my old windows would heat the house up to 80+ degrees. Now my house stays in the high 60s low 70s without AC. They look great and have a slim frame for maximum viewing. I could not be happier with the choice I made. Bottom line here, if you need windows or even custom window work, call Jay. You will not be disappointed! In fact, maybe call Jay last after you have dealt with all the others in your bidding process. You will see what I mean. read more

I can't say enough good things about Centennial Home Improvements. Jay has installed all of our windows at four homes over the past five years, and the older windows still look and work just like the new ones. They have helped with insulation and especially noise. We have neighbors who play loud music and now with the windows closed we can't even hear it. It's amazing what a difference there is in ease of use (they pop out to clean), noise control, and heating/cooling over the home's original windows. Jay's excellent service, attention to detail, five star work crew, and low prices are unbeatable. If you are in the market for high-quality vinyl windows, I highly recommend you get a quote from him before making a decision. read more

I was in the market to have 6 windows replaced originally because I thought that's what I could have afforded with my budget. Jay was the second person I called to get a bid and his bid was much lower than the first company I contacted so I added two more windows. He explained to me that since he's the owner himself, he was able to give me a much better price without the salesperson. His bid for 8 windows total was still lower than the first bid I got and those are for the exact same models so I knew it was comparing apples to apples. On top of the honest and very competitive pricing, he came out in a spring snow storm weather on a Saturday to give me the quote and patiently answered all my questions. Jay was really good at communicating with me throughout the whole process. The installers came out and installed 8 windows for me today. They were as good as I could have expected, professional and efficient. They did a good job cleaning up the work site and the windows are as good as Jay had advertised. If you are in the market for replacement windows, you really should give Jay a call. He will most likely give you a very competitive bid to begin with and has no problem matching and beat other people's bids for the same windows. One lesson I learned from this experience is to get several bids once you have decided on what windows to get and I was happy that I did and found Jay in the process. read more