20 Best Window Companies in Westmont, CA (2025 Reviews)
Looking to replace your home's windows? We’ve got you covered in this list of the best window installation companies.
We analyzed all the top-rated window companies in Westmont and selected the best 20 based on:
Customer reviews
Window installation expertise
Popularity with home-owners like you
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Why you can trust EcoWatch
Although clean energy sources like wind and solar are important when it comes to decreasing your carbon footprint, improving your home’s energy efficiency can also have a big impact on home energy conservation. During the hot summer months, the last thing you want is your cool air to leak out of your outdated windows.
Thankfully, helping you save energy with efficient windows also aligns with our goals of reducing energy usage for the environment.
Unlike other review sites, EcoWatch ranks window installation companies based on energy efficiency while also taking into consideration cost, customer satisfaction and service area.
Best Availability
Renewal by Andersen
- Great Industry Reputation
- Award-winning Company
- Member of US Green Building Council
- Manufactures products in-house
Power Home
- Uses eco-friendly materials
- Well-trained, certified installers
- Lifetime or lengthy warranty
Best for Residential Windows
Window Nation
- Custom Designs
- Wide variety of products and services
- Manufactures products in-house
Best Window Installation & Replacement Companies in Westmont
The EcoWatch team assessed several window companies in Westmont to find the best ones for our readers. We assessed the installers based on energy-efficient offerings, customer service, coverage area, local experience, price and more.

Window World
EnergyStar Partner
Large serice area
Low prices relative to competitors
Great industry reputation
Lifetime warranty
Quality of service will depend on your area
Window World is the largest window replacement company in the country, known for its vinyl windows and affordability. This company has 27 years of experience in the windows industry, and it has proved to be one of the most respected companies in Westmont. The provider has hundreds of glowing reviews from customers online.
You may want to consider choosing Window World if you're looking for a company that is certified by the Environmental Protection Agency (EPA) and Energy Star and supports charities like St. Jude Children’s Research Hospital.
Energy Efficiency of Window World WindowsWindow World carries some Energy Star windows, but note that not all its windows are energy-efficient, so make sure you mention that you want Energy Star windows when inquiring. Its high-performance Low-E (low-emissivity) coatings and argon gas insulation offer exceptional efficiency and performance for any home.
How much does Window World cost in Westmont?Although prices are not readily available on Window World’s website, it's known for offering some of the most affordable window installations around. Getting a free quote on its website is the best way to get more accurate pricing information.

Milgard Windows & Doors
EnergyStar Partner
Wide network of installers
Lifetime warranty available
Entails hiring third-party contractors
Limited additional services
Milgard Windows & Doors is a family-owned and -operated window replacement company, which primarily serves the West Coast. This company has 60 years of experience in the windows industry, and it has proved to be one of the most respected companies in Westmont. The provider has hundreds of glowing reviews from customers online.
You may want to consider choosing Milgard if you're looking for a company that offers competitive pricing, a comprehensive warranty and installers that all have a minimum of 15 years of window installation experience.
Energy Efficiency of Milgard Windows & Doors WindowsMilgard Windows & Doors carries some Energy Star windows, but note that not all its windows are energy-efficient, so make sure you mention that you want Energy Star windows when inquiring. The company manufactures its own products, which gives it the freedom to make custom windows based on the climate. The company designs its own vinyl compounds and profiles to ensure a heat-stable product that performs as advertised.
How much does Milgard Windows & Doors cost in Westmont?Although prices are not readily available on Milgard’s website, it offers different kinds of windows at varying price points. Getting a free quote on its website is the best way to get more accurate pricing information.

Renewal by Andersen
Great industry reputation
Award-winning company
Member of US Green Building Council
Manufactures products in-house
No lifetime warranty
More expensive than competition
Renewal by Andersen is a subsidiary of the Andersen Corporation, a major manufacturer of windows and doors. This company has 27 years of experience in the windows industry, and it has proved to be one of the most respected companies in Westmont. The provider has hundreds of glowing reviews from customers online.
You may want to consider choosing Andersen if you're looking for a company that uses in-home estimates and advanced digital tools to help you plan and visualize your project before getting started.
Energy Efficiency of Renewal by Andersen WindowsRenewal by Andersen carries some Energy Star windows, but note that not all its windows are energy-efficient, so make sure you mention that you want Energy Star windows when inquiring. A handful of windows manufactured by the Andersen corporation were awarded Energy Star’s “Most Efficient” in 2021, and Andersen was named Energy Star’s Partner of the Year in 2019.
How much does Renewal by Andersen cost in Westmont?Although prices are not readily available on Andersen’s website, based on customer feedback, you can expect to pay anywhere between $750 to $1,250 per window for an installation with Andersen. Getting a free quote on its website is the best way to get more accurate pricing information.
One thing to note is that the companies in this section are national, which means the quality of customer service may vary depending on your local team. We have tried to be unbiased and transparent by including pros and cons for each provider.
More Window Companies in Westmont
Renewal by Andersen of Los Angeles
Torrance, CAFinancing options available
Price Transparency
Educational Website
Good Customer Service
In-home or virtual consultations
Free assessment
31,000+ projects completed
Services Offered
Skylights
Window Replacement/Installation
Bay Windows
Double-Hung
Glass Doors
Discount Window And Door
Redondo Beach, CAFree assessment
Good Customer Service
Price Transparency
Services Offered
Glass Doors
Energy-Efficient Options
Vinyl Frames
Window Replacement/Installation
Skylights
Metal Frames
Smart Window Company
Torrance, CAGood Customer Service
Educational Website
Price Transparency
Free assessment
Services Offered
Energy-Efficient Options
Glass Doors
Window Replacement/Installation
Double-Hung
Vinyl Frames
Tempered Glass
Harbor Construction
Huntington Beach, CAPrice Transparency
Timely Service
Educational Website
Free assessment
Good Customer Service
Services Offered
Energy-Efficient Options
Bay Windows
Vinyl Frames
Glass Doors
Double-Hung
Window Replacement/Installation
Concierge Home Remodeling
Tarzana, CAEducational Website
Free assessment
Price Transparency
Good Customer Service
Services Offered
Window Replacement/Installation
Energy-Efficient Options
Dede Windows and Doors / window replacement
Anaheim, CAFree assessment
Educational website
Educational Website
Energy-efficient windows and doors
American-made vinyl
Price Transparency
Good Customer Service
Services Offered
Window Replacement/Installation
Vinyl Frames
Glass Doors
Custom Window Designs
Hometime Windows & Doors
Glendora, CAGood Customer Service
Free assessment
Price Transparency
Educational Website
Services Offered
Window Replacement/Installation
Glass Doors
Energy-Efficient Options
SoCal Window Pros
San Dimas, CAEducational Website
Free assessment
Good Customer Service
Services Offered
Window Replacement/Installation
California Window & Solar
Costa Mesa, CAFree assessment
Good Customer Service
Educational Website
Price Transparency
Services Offered
Metal Frames
Vinyl Frames
Window Replacement/Installation
Energy-Efficient Options
Glass Doors
Golden Age Builders
West Hollywood, CAPrice Transparency
In-home consultations
Unique window options
Timely Service
Good Customer Service
Free assessment
3D design and planning tool
Services Offered
Window Replacement/Installation
CGH Solutions - California Green Home Solutions
Van Nuys, CAEducational Website
Price Transparency
Good Customer Service
Services Offered
Vinyl Frames
Energy-Efficient Options
Double-Hung
Window Replacement/Installation
Glass Doors
Save-On Glass & Screen
Westminster, CATimely Service
Good Customer Service
Free assessment
Services Offered
Window Repair
Glass Doors
Mirrors
Window Replacement/Installation
Glass Showers
Best Windows and Doors OC
Anaheim, CAPrice Transparency
Free assessment
Good Customer Service
Educational Website
Services Offered
Vinyl Frames
Window Replacement/Installation
Custom Window Designs
Glass Doors
Window King
Huntington Beach, CAFree assessment
Educational Website
Price Transparency
Services Offered
Energy-Efficient Options
Double-Hung
Window Replacement/Installation
Glass Doors
Vinyl Frames
TMC Windows & Doors
Orange, CAPrice Transparency
Good Customer Service
Free assessment
Services Offered
Glass Doors
Window Replacement/Installation
Energy Core Construction
Anaheim, CATimely Service
Price Transparency
Educational Website
Free assessment
Good Customer Service
Services Offered
Bay Windows
Window Replacement/Installation
Glass Doors
Energy-Efficient Options
Mancino Door & Window, Inc.
Glendora, CAPrice Transparency
Free assessment
Educational Website
Services Offered
Window Replacement/Installation
Can-Do Windows & Doors
Santa Ana, CAFree assessment
Educational Website
Price Transparency
Services Offered
Glass Doors
Energy-Efficient Options
Vinyl Frames
Wood Frames
Metal Frames
Window Replacement/Installation
Fiberglass Frames
Double-Hung
American Vision Windows
Simi Valley, CAFree assessment
Educational Website
Price Transparency
Services Offered
Double-Hung
Bay Windows
Vinyl Frames
Glass Doors
Energy-Efficient Options
Wood Frames
Window Replacement/Installation
Fiberglass Frames
Home Upgrade Specialist Inc
Los Angeles, CATimely Service
Price Transparency
Free assessment
Wide range of services
Financing options available
Energy-efficient products
Educational Website
Good Customer Service
Services Offered
Energy-Efficient Options
Window Replacement/Installation
Calculate how much you can expect to pay for window installation and replacement in Westmont, CA using our customized window cost calculator.
Estimates will vary based on window dimensions and other unique factors to your home. Getting in touch with a local window installer is the best way to get an accurate cost estimate for your home.
How Installing Energy-Efficient Windows in Westmont Saves You Money
There are several benefits of upgrading to energy-efficient windows. Some reasons you may want to consider making the switch include the following:
- Decrease your carbon footprint: Because energy-efficient windows improve the insulation in your home, you can reduce your carbon footprint by about 12%, according to Energy Star.
- Protect your investment: When you have an older home, your windows could also be outdated or damaged. Upgrading your windows is an important part of maintaining your property and its value.
- Save money on power bills: Switching to energy-efficient windows reduces your energy bills by about 12% because you use less energy.
- Protect your valuables from fading: The low-emissivity coatings on some energy-efficient windows filter out harmful UV rays, preventing your furniture, carpet and other valuables from fading.
Estimated Cost of Window Replacement in Westmont
Each window replacement company provides various services and has varying costs based on a few factors.
How Much Do New Windows Cost?
Typically, Westmont homeowners can expect their window replacements to range from $250 to $1,200. The average cost is at around $600. How much it will cost is based on several factors, like type, material, the location of your home, number of windows, size and more.
With windows, efficiency is the most important factor for most homeowners. High efficiency windows may cost more off the bat, but by increasing the efficiency of your home — particularly if you live in a hot climate — they can give you many years of energy savings. According to Energy Star, buying certified energy-efficient windows can save Westmont homeowners $509+ each year after replacing single-pane windows.
Something else that affects the overall cost is the material of the frame you select. Aluminum frames are generally the least expensive and are sturdy and relatively maintenance-free, but they offer poor insulation. On the other hand, wood frames cost the most because they are aesthetically pleasing and provide decent insulation. Fiberglass and vinyl frames provide good insulation as well and cost somewhere between the other two.
What Services do Window Installers Offer?
The first step when considering an installation is to figure out whether you should get a full-frame or pocket installation.
Full-frame installations require replacing the whole window — the sill, frame, trim and all. These are typically done when you want a new style for your windows or when it has significant rot or deterioration. Full-frame installations involve more time and labor and will increase overall costs. Pocket installations (also known as retrofits) are when you replace a window within its existing frame. Pocket installations are simpler and won’t carry as large a bill, but you can’t do this type of installment if you have any pre-existing rot or water damage.
If you’re still trying to decide which type of installation to get, you can consult with your provider and get their recommendation. The decision mostly is influenced by how old the frames are and if there’s any damage present.
Best Availability
Renewal by Andersen
- Great Industry Reputation
- Award-winning Company
- Member of US Green Building Council
- Manufactures products in-house
Power Home
- Uses eco-friendly materials
- Well-trained, certified installers
- Lifetime or lengthy warranty
Best for Residential Windows
Window Nation
- Custom Designs
- Wide variety of products and services
- Manufactures products in-house
How We Choose the Best Window Installers in Westmont
In our hunt to find the most reliable, eco-friendly window installers in Westmont, EcoWatch examined dozens of companies before deciding on these. We’ve evaluated the top window replacement companies in Westmont mostly based on energy efficiency, as it’s the most sustainable option and the best one for homeowners. Energy-efficient windows can cut your power bills by hundreds of dollars. Along with energy efficiency, our rating methodology takes the following factors into consideration:
Service Area
Since this is a guide for Westmont, we gave more points to companies that cover the city. There are certainly reputable providers that didn’t make the list because of the low odds that they would serve the average homeowner in Westmont.
Work Quality
We’re willing to bet that you’re not looking for a company to do a shoddy job installing windows. We’ve vetted each company featured in our guide to ensure its contractors are well-qualified and that the company has gotten a lot of positive customer feedback to vouch for its service.
Customer Reviews
Customer feedback is another super important review factor. If most customers don’t have good feedback about their experience with a certain company, you won’t see it featured on EcoWatch.
Cost
This one is a give-and-take: as with most services, cheap window installation companies won’t always provide the most quality service. Still, we want to make sure we’re highlighting companies that offer a spectrum of price and financing options so they’re accessible to most homeowners.
Warranty
Protecting your investment in new windows is important. For that reason, window installation companies that have lengthy warranties for products, parts and labor rank higher with EcoWatch.
Years of Experience
Due to Westmont’s climate, homeowners need to be wary of rot, low efficiency and water damage. We factored in local experience to reflect the ability of Westmont window companies to prepare homes for these issues. If a company has less than 10 years of experience, it loses points in this category.
Westmont, CA Window Replacement FAQs
How much should window installation cost?
The national average cost to install one window is about $600 but can range between $200 and $1,200, based on several factors. The price is generally influenced by the type and material of the window, the size of the window and the location of your property. Also, bear in mind that energy-efficient windows may cost more upfront but can save you hundreds of dollars a year in energy bills.
What are the most common types of replacement windows?
The most common types of windows for homes are double-hung and single-hung windows, casement windows, transom windows, picture windows, awning windows, bay windows and slider windows.
What do window installers do?
Window installers go to your home to remove your old windows and replace them with new ones. Some providers install products manufactured by other companies, whereas others are both manufacturers and installation companies combined. The installer will also clean up after the installation.
Should I replace my windows all at once?
If your windows are more than 20 years old, it’s most likely time to replace all of them. By that point, they are typically less efficient, leakier and/or more damaged than new windows. Replacing your windows all at the same time will involve less paperwork and less stress.
How long does it typically take to install windows?
Each window takes about 30 minutes to install depending on the kind of window. However, the window installation can take two days or more if you need to have a lot of windows installed.