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Marathon Windows Ltd

4.9

177 Reviews

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About

Marathon Window Company - Installers of high quality thermally efficient double glazing products since 1975. Surreys leading specialist in designing and installing conservatories, orangeries, garage conversions, double glazing windows and replacement doors.

What we do

  • Double glazing

    • Double glazing installation
    • Double glazing repairs
    • Double glazing suppliers
  • Conservatories

  • Doors

    • Bi-fold doors
    • Composite doors
    • Front door
    • Patio doors
    • French doors
    • Orangeries
    • UPVC doors
    • Timber doors
  • Glaziers

    • Replacement window services and repairs
    • Sash windows
    • Aluminium Windows
    • Window consultants
  • More Services

    • plantation shutters

Customer reviews

Why you can trust these reviews

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4.9
177 reviews
Customer Service
5.0
Quality
4.9
Value
4.9
Sort by
Replacement Window Units
Customer Service
Quality
Value
16 units of differing sizes replaced. All staff, from office - survey - installation great to deal with. Units built & ready for instal quicker than I expected. Great efficient job done. No hesitation about using again - recommended.
Customer in Surrey Posted on 16/11/2025 , work completed 10/11/2025
Excellent company
Customer Service
Quality
Value
I was very impressed by the professionalism every step of the way as well as the fair pricing. Marathon windows replaced our doors and windows downstairs and our double glazed glazing upstairs. Their communications were accurate at all stages from first contact to payment receipt, they turned up punctually and completed the job in a timely manner. The two fitters were skilled and friendly and enjoyed their tea!
Customer in Greater London Posted on 31/10/2025 , work completed 29/10/2025
Replacement windows and doors
Customer Service
Quality
Value
All the staff were pleasant and helpful. The quote was reasonable compared with another. The fitters were polite, cheerful, moved 1 heavy item of furniture that I could not and cleared up at the end of each day. A deposit was required before start and they invoice promptly but was not hassled to pay quickly when I delayed the last payment for a few days until a missing item was fitted. The windows and doors now look very smart.
Customer in Greater London Posted on 01/09/2025 , work completed 27/08/2025
Experienced and efficient workers
Customer Service
Quality
Value
We had a back door and an upstairs bay window fitted. The window in particular was very tricky since it supported whole of the roof overhang. We felt very confident that we were in good hands. Everyone from the Surveyor to the fitters were very professional, knowledgeable and hard working and made sure that everything was perfectly in order before they left. Friendly but polite and considerate. Would not hesitate to use them again.
Customer in Surrey Posted on 09/08/2025 , work completed 17/07/2025
Good service
Marathon fitted a back door and window always do a nice job and any problems will always resolve them and comeback which is always good we have used them before always great to deal with and great customer service from all the team great local company
Customer in Surrey Posted on 31/05/2025 (Reviewer did not use service)
Replacement windows
Customer Service
Quality
Value
We were so pleased with the first order of replacement windows and new front door that Marathon had installed previously that we did not consider any other company to fit more replacement windows. From initial assessment to final fitting everything was carried out in a friendly and efficient manner. The problem we had had with our bay window was solved and we no longer have issued with damp patches underneath. We have pleasure in wholeheartedly reccommending Marathon Windows.
Customer in Surrey Posted on 19/03/2025 , work completed 10/01/2025
Lovely new front door
Customer Service
Quality
Value
Great, prompt guys fitted our front door. Very efficient, professional and friendly. Lovely quality door. Jane is very helpful and friendly. I would recommend marathon windows.
Customer in Surrey Posted on 03/03/2025 , work completed 02/01/2025
Fabulous!
Customer Service
Quality
Value
Marathon were fab. The lady who came for the first measure-up was brilliant, understanding aesthetics and balancing costs, as well as talking through legal technicalities like fire openings. Compared with other companies we saw, it was chalk and cheese. And to cap it all, they came out best on price too, so there was no decision to make! On the day the guys were fabulous – dust sheets everywhere so no mess or dust, very considerate at keeping disruption to a minimum, and were finished earlier than planned. All great from start to finish and I’ve already recommended them to friends!
Customer in Greater London Posted on 24/02/2025 , work completed 11/02/2025
Very satisfied
Customer Service
Quality
Value
Marathon windows replaced 2 existing metal double-glazed windows on the second floor of the house. The windows were installed without needing scaffolding and are a major improvement on what we had previously. The company was helpful and efficient throughout, and the work was done on time and without leaving any mess.
Customer in Surrey Posted on 07/02/2025 , work completed 17/12/2024
Good service with conscientious and courteous employees
Customer Service
Quality
Value
Excellent service throughout. No issues other than our house had difficult access. They found a way to get 4 bifold doors to the back of the property on the day and finished to a very high standard. A local company and one I would urge local people to support.
Customer in Surrey Posted on 08/12/2024 , work completed 03/12/2024
new windows
Customer Service
Quality
Value
Marathon installed 6 wooden sash windows for me. There is a long lead in from ordering to installation, but that's because the windows have to be specially made to order from another manufacturer, so I was expecting that. The guys that came to install them were really good, the installation went smoothly and when they did encounter problems they solved them - the windowsill outside on the bay window was rotten and fell apart when they took the old windows out so they made a new sill in hardwood and fitted it beautifully and then got a painter in to paint the sill and some other areas. All in all very pleased.
Customer in Surrey Posted on 18/11/2024 , work completed 18/11/2024
Excellent again from Marathon
Customer Service
Quality
Value
We have no hesitation in recommending Marathon Windows. This is the fourth time we’ve used them as we have moved house. They come down to West Sussex and have fitted all new windows and doors for us. The service from Tony when measuring is excellent and the fitters are all cheerful and friendly. No mess left in the house at the end and all windows work perfectly.
Customer in West Sussex Posted on 14/11/2024 , work completed 24/10/2024
Replacement front of house windows - Amazing job
Customer Service
Quality
Value
My husband installed our front windows some 40+ years ago and it was time for them to be replaced. We were recommended Marathon Windows (a family run business) by a neighbour. Mum (Jane) came to quote, Dad (Tony) came to survey & measure and, within 6 weeks, Son (Luke) came to install. We were informed that the upstairs front windows would be replaced on the first day and the downstairs the second day and that’s exactly what happened. Luke, Jack and Les were so professional: punctual arrival time - with only a short break for lunch - respectful use of dust sheets and, at all times, polite and cheerful. Our windows now look spectacular and the boys left everything neat and tidy – both inside and outside. It honestly looked like no-one had been in the house at all! You could see they took great pride in their work – and it showed. Incredible service from start to finish, we cannot fault them at all. Without hesitation, we highly recommend this wonderful family business.
Customer in Greater London Posted on 29/09/2024 , work completed 25/09/2024
Excellent service for window replacement from Marathon
Customer Service
Quality
Value
Replaced the main Window in our conservatory and another window in one of our bedrooms. Polite, clear guidance, reasonable prices, timely completion and clean way of working. Cannot fault Marathon and would definitely recommend.
Customer in Surrey Posted on 12/09/2024 , work completed 23/08/2024
Excellent service.
Customer Service
Quality
Value
From start to finish our experience with Marathon Windows was nothing but positive. We had a problem with existing bay window which was diagnosed by the surveyor. A new bay was fitted by their expert workmen who were friendly and proficient - and left no mess. We also had a beautiful new front door fitted with the same proficiency. We considered the price of both window and door to be extremely fair and the experience was completely stressless. We have no hesitation in recommending Marathon Windows and will certainly use them again.
Customer in Surrey Posted on 17/08/2024 , work completed 16/07/2024
Helpful and Efficient.
Customer Service
Quality
Value
Marathon windows from start to finish, were helpful, friendly and efficient. Jane visited my house on the 9th July to discuss my requirements. Jane offered very practical and helpful advice. I received a quote by e mail on the same day. My quote was competitively priced. I was given a timescale of work, and Jane was always available to speak to with any queries. The work was completed ahead of the timeframe and I am absolutely delighted with my new windows and doors. A big shout out to Paul and Anthony who completed the work, they were friendly, polite and informative. All work was completed to a high standard and my home was left very clean. I would definitely recommend Marathon windows.
Customer in Surrey Posted on 16/08/2024 , work completed 16/08/2024
Marathon windows company
Customer Service
Quality
Value
I was very pleased with the attitude and performance of the company from asking for a quotation to the completion of the installation. They kept to the date given for installation. The installers were both excellent. They took their time to provide an expert installation of the bay windows in the children’s bedroom. They cleaned the room after install and took all the rubbish away.
Customer in Surrey Posted on 15/07/2024 , work completed 03/07/2024
I'm delighted with my new door. A great job completed on time and to budget.
Customer Service
Quality
Value
I am delighted with the work carried out by Marathon. My sash window has been replaced by a door, giving me direct access into our communal gardens and a lot more light. I'm already making friends with the foxes! The fitters were a great couple of lads; always on time, hard working, polite and scrupulously clean. From the initial visit, the follow up to take measurements and then the installation, everything went without a hitch. I would have no hesitation in recommending Marathon, a thoroughly professional outfit.
Customer in Surrey Posted on 25/06/2024 , work completed 12/06/2024
Windows and Front Door Replacement
Customer Service
Quality
Value
Excellent service, friendly team, responded to requests promptly and efficiently. Would recommend Marathon Windows for any Window or Door Replacement/ Repairs.
Customer in Surrey Posted on 25/06/2024 , work completed 01/05/2024
Replacement Back Door
Customer Service
Quality
Value
Marathon were called in for a quotation to replace a rotting back door, complete with new frame and sill.. The work proceeded a few weeks after acceptance and was carried out by Adam and Anthony who did a splendid job which met all my expectations. Everything was left very clean and tidy.
Customer in Surrey Posted on 15/04/2024 , work completed 25/03/2024
Perfect installation
Customer Service
Quality
Value
Marathon promptly provided a quotation with lots of options Having guided us through the options we decided to proceed The target date was met and the installation team were exemplary All the boxes were ticked and problem free
Customer in Surrey Posted on 04/01/2024 , work completed 14/12/2023
Excellent Job
Customer Service
Quality
Value
Marathon Windows replaced all our double glazing and front and back doors. From the beginning to the end, it was a pleasure to use Marathon Windows. Jane, who came to do our quote, was terrific — giving us great advice and suggestions. She was genuinely interested in providing what was best for us, not just making a sale. The installation team (Adam and Anthony) were friendly, efficient, and very tidy. Our new doors and windows are all of excellent quality and look wonderful. Couldn't be happier or recommend them more highly. Thanks again, Which for another fabulous company.
Customer in Surrey Posted on 20/12/2023 , work completed 28/11/2023
Super job
Customer Service
Quality
Value
We are really pleased with our whole house window replacement from quotation through to completion. Such a neat job. Dust sheets everywhere. Cleaned up afterwards. No making good needed on inside and minor painting over small areas of render on outside will be needed. Also done in good time. Compliments to your installation team, Luke, Jack, Les and Adam. Would have no hesitation in recommending Marathon to anyone.
Customer in Surrey Posted on 15/09/2023 , work completed 30/08/2023
Replacement glass and new garage door
Customer Service
Quality
Value
Initial quotation process was good, engineer arrived on time and was quick and precise, no problems good work, very reasonable quotation. Good delivery time, called to arrange installation very reasonable time scales. Installation engineers very good, clean and tidy, professional installation and very quick to be honest, knew what they had to do and done it. Cleaned up after all very good, no complaints.
Customer in Surrey Posted on 11/08/2023 , work completed 04/08/2023
Great Job
Customer Service
Quality
Value
They installed windows on my period property look fabulous & in keeping with its character. I am very pleased with the service, quality, finish & price and would definitely recommend Marathon to anyone thinking of having new windows installed. Their after-sales service is very good too. I chose Marathon as they were recommended to me by a couple of friends who had work done on their properties and I am so glad I did. The owners are charming & friendly and were a pleasure to work with.
Customer in Surrey Posted on 20/07/2023 , work completed 05/07/2023