Endorsed by Which?

London Box Sash Windows Ltd

5.0

140 Reviews

Opening Hours
Today - 07:30–13:30
  • Monday 07:30–13:30
  • Tuesday 07:30–13:30
  • Wednesday 07:30–13:30
  • Thursday 07:30–13:30
  • Friday 07:30–13:30
  • Saturday - Closed
  • Sunday - Closed

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About

London Box Sash Windows is a family-owned and operated business that has been providing London homeowners with high-quality, custom-made timber sash windows for over 40 years. We use only the finest timber and double-glaze our windows to provide excellent insulation and energy efficiency. Our windows are also built to the highest standards and are backed by a comprehensive warranty.

We offer a wide range of timber sash window styles to choose from, including horns to match existing designs, traditional looking double-glazed units, casement windows and french doors

If you are looking for high-quality, custom-made timber box sash windows, then London Box Sash Windows is the perfect choice for you. Contact us today to schedule a free consultation and estimate.

FENSA Registered Company

0208 648 4230

What we do

  • Glaziers

    • Window consultants
    • Sash windows
    • Replacement window services and repairs
    • Timber windows
  • Double glazing

    • Double glazing installation
  • Carpenters

    • Joinery and carpentry
  • More Services

    • double-glazed timber sash windows

Customer reviews

Why you can trust these reviews

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100% of the reviews we publish have been through our stringent moderation process.

5.0
140 reviews
Customer Service
5.0
Quality
5.0
Value
4.9
Sort by
Fantastic windows and service
Customer Service
Quality
Value
London Box Sash replaced all the sash windows at the front of my Victorian house including a dormer, and a kitchen casement window. Every aspect of this company’s service was friendly, efficient and highly professional. The windows themselves are perfect with a 50 year guarantee and the fitters were extremely competent and completed the task very quickly. They also took exacting care not to leave any mess, building a floor to ceiling screen around all the work and covering every inch of floor. I was particularly impressed with the initial survey, where my needs were listened to so that what was installed exactly met my requirements. I chose the company’s ‘standby’ offer since I wanted the work done fairly quickly, and they were accommodating enough to fit it within the dates I could do. The customer service was also everything I could ask for, and when a blind couldn’t be refitted and there was a problem with rehanging a curtain rail, I was compensated. It was one of the higher quotes I received, but completely worth it, and the standby reduction made a difference. I can’t recommend more highly.
Customer in Greater London Posted on 14/07/2026 , work completed 02/07/2026
Perfect service - fast, reliable and friendly
Customer Service
Quality
Value
Whilst the quote was slightly higher than some others, the quality of these windows stood out and the team were incredible with communication, helped me make decisions that saved me money, and also booked the job in asap as a priority due to my childs window being broken and really needing to be replaced before bad weather arrived. Every member of the team was friendly, helpful and reliable. they stuck to dates and even finished early. There was not even any redecorating needed to be done post installation. Highly recommended
Customer in Greater London Posted on 03/07/2026 , work completed 01/07/2026
Great job
Customer Service
Quality
Value
All seamless from start to finish. Communication was excellent. Fitters were polite , friendly, hard working and stayed late when needed to make sure everything was finished properly for the day. They took great care in our home, covering all the furniture to minimise dust and disruption as much as possible. The back room staff were also fantastic- organised, helpful and always quick to follow up on any queries we had, which made us feel reassured throughout that we had made the right choice. We are absolutely delighted with the finished result and would highly recommend this company to anyone considering new windows.
Customer in Greater London Posted on 08/05/2026 , work completed 23/04/2026
Professional service
Customer Service
Quality
Value
A sash window was replaced in my late 19th century flat conversion. The estimator, surveyor, installer and phone receptionist were all professional and the work was carried out on time and to budget. The new window was close to the same style as the original (save slightly larger frames to accommodate double-glazing).
Customer in Greater London Posted on 20/04/2026 , work completed 10/04/2026
Beautiful windows, excellent service!
Customer Service
Quality
Value
I have a number of properties that needed the old aluminium windows. London Box Sash have done a fantastic job. I have used their service about four times now. Each time, I have shopped around and each time, London Box Sash has been the best company by far - competitive on price, service and aesthetically pleasing products. Firstly, they have gorgeous windows, with a wide range of hardware. I have had both sash windows and casement windows installed - they use the highest quality accoya wood. Secondly, the installers always do a really good job of making good around the windows - be it wall paint or tiles - after installation, ensuring that the work doesn't look half finished. The installers arrive on time, they are respectful of the home and work really quickly and professionally. Often, installation would be all done in half a day. Thirdly, the whole process of ordering windows, to survey and installation date is smooth and helpful. Everyone from Judith in the office who takes care of payment to Harry and Jake who arrive to measure and survey, it has the feel of a family business, and there are always the same people on hand, ready to help. Furthermore, their knowledge of windows and its materials is impressive - and they always provide advice on what works best. Lastly, the aftercare is excellent. For any challenging window installations (and there were a few for my wonky Victorian walls), they will problem-solve and arrive at the drop of a hat to fix!
Customer in Greater London Posted on 10/04/2026 , work completed 24/03/2026
Excellent service and elegant sash windows
Customer Service
Quality
Value
We recently had our sash windows installed by the London Box Sash Window Company, and the whole experience was excellent. Anjelo and Raf, the installation team were respectful, professional, and did a wonderful job. Jake who looked after us on the sales side, was helpful and knowledgeable, Judith kept it all organised. The sash windows themselves look absolutely beautiful and have completely transformed the appearance of the house. We've had a number of compliments from people passing by, which speaks for itself.
Customer in Greater London Posted on 20/03/2026 , work completed 20/02/2026
Perfection every time
Customer Service
Quality
Value
I would never use another company other than London Box Sash. Having used them for many years on many projects, i can safely say you are in good hands. From the initial consultation to the final fit, everything is smooth and professional. The fitting is exemplary and the result is perfection. In my mind no one does wood windows like this company and the workmanship and quality of the product is second to none. I would never hesitate in recommending them and whilst they may be a little more expensive than other suppliers and fitters, rest assured it is because their products are superior. Another major feature of their windows is the quality and longevity of their paint and wood choice they use. My original windows are well over 10 years old. No cracking of the wood or paint and they look brand new, just like the day they were fitted.
Customer in Greater London Posted on 17/03/2026 , work completed 14/01/2026
An extremely satisfied customer
Customer Service
Quality
Value
I had two windows replaced - I was impressed by the workmanship and expertise of the fitters but also the p sales, planning /measuring and advice I was given including the office support customer service and care . The windows look wonderful and work extremely well. I would recommend this company to anyone considering replacing their sash windows with double glazed wooden windows. They are a company to be trusted.
Customer in Greater London Posted on 13/03/2026 , work completed 11/03/2026
London Box Sash Windows
Customer Service
Quality
Value
I have used London Box Sash Windows Ltd over the last few years for upgrading nearly all the windows in my house and wouldn't go anywhere else. I have also passed them on to friends and family, all of whom have been just as satisfied. Their work is first class and they are professional, polite, hard working, clean and tidy.
Customer in Greater London Posted on 09/03/2026 , work completed 20/02/2026
Excellent quality, value for money, fantastic customer service
Customer Service
Quality
Value
We have used London Box Sash Windows twice. The sales team are easy to contact, clear about the process and prices and helpful in answering follow up questions. The window fitter, who has done both jobs, has always been punctual, friendly, efficient and highly skilled at his job. The quality of the sash windows is amazing- they look brilliant and have improved the heat retention and light in every room. We would not hesitate to use them.
Customer in Greater London Posted on 08/03/2026 , work completed 27/02/2026