“I was kept informed at every stage of the project” · Which? Trusted Traders
“quick response times” · Which? Trusted Traders
“Judith kept it all organised.” · Which? Trusted Traders
Public evidence profile · Checked July 2026
London Box Sash Windows Ltd
Credentials & registries
2 credentials shown
Trust Score
58out of 100
- Rated 5.0 from 141 reviews
- 2 credentials shown
How this score is worked out
Rating5.0 / 5
Review volume141
Independent sources2 independent public sources
Credentials2 credentials shown
How this score is made up
What customers say43.3 of 60
Independent checks13.4 of 30
Track record1.3 of 10
See the independent checks
- Licences and credentials4.1 of 8.3
- Ways to reach them8.3 of 8.3
- Reviewed on more than one site0 of 6.2
- Registered company details0 of 4.1
- Photos of their work1 of 2.1
- Industry recognition0 of 1
Missing evidence lowers the score because we can't check it. It doesn't mean it doesn't exist. Claiming a profile never changes the score. Evidence context, not a guarantee of workmanship.
Trust at a glance
1 checkWhat we can verify about London Box Sash Windows Ltd
Each card sums up one thing we can check from public sources. Open it for the full detail and the named source. This is evidence context, not a guarantee.
See the full verification checklist for London Box Sash Windows Ltd →Reviews · public evidence
What customers say
These review totals are published independently on the named public source below, not testimonials this business chose to show. We show the aggregate rating, review volume, and source attribution we hold so you can weigh the evidence yourself.
5.0out of 5
Customers often mention
Where these reviews are published
- Which? Trusted Traders141 reviews · 5.0 avg
From customer reviews
What customers consistently say
Recurring themes from 25 customer reviews on Which? Trusted Traders.
Respectful and tidy in your home: “installers were not only efficient but left everything spotless” · Which? Trusted Traders
“He arrived on time every day” · Which? Trusted Traders
“The tradesperson arrived on time, on the designated dates.” · Which? Trusted Traders
“The installers arrive on time” · Which? Trusted Traders
Credentials and associations
2Credentials and memberships
These credentials and memberships are attributed to named public sources. Check the source before relying on them.
- Source reference
- 4278
- Source checked
- 25 Jul 2026
- Source checked
- 25 Jun 2026
Source-listed gallery
17 photosPhotos listed on Which? Trusted Traders
These sources do not label every image as completed work. The gallery may include projects, people, logos or certificates, so it does not count as completed-work evidence.
Finalists
Wandsworth
Twickenham
Michael morticing one of our sash windows with mm precision
George applying the finishes touches to this sash window before it goes for installation
Black sash windows installed to the Bryant Building in Shoreditch - EC1
Accoya Sash window painted in Farrow & Ball colours, installed in Raynes Park - SW20
From Which? Trusted Traders
Opening hours
The hours this business publishes online, handy for knowing when to call. Confirm before you set off.
- Monday–Friday
- 7:30am–1:30pm
Sources
4 named public sourcesWhere this information comes from
Everything on this page is drawn from named public sources. Where a source provides a public link, you can open the original and dig deeper.
Review sources
Registers and membership directories
Business and public registers
Public evidence last checked July 2026
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
Services they list
Window consultantsSash windowsReplacement window services and repairsTimber windowsDouble glazing installationJoinery and carpentrydouble-glazed timber sash windows
Listed on public sources or the business's own website; check directly that they cover your job before you book.
What this business says about itself
From their own website
What this business says about itself
See their work: Photo gallery (opens in new tab) · Facebook (opens in new tab)
- Good to know: Family-run
Accreditations it displays. Confirm each is current on the official register before you hire:
- Which? Trusted Trader · verify (opens in new tab) · we hold this registration
- FENSA · verify (opens in new tab) · we hold this registration
These are statements the business makes on its own website, worth confirming in writing (and on the official registers) before you hire, not independently verified by us.
Independent checks
About this business
Website online sinceTheir website domain has been registered since 2010, according to the public domain registry. This dates the website, not necessarily the business.
Your own checks
What to check before you hire
Worth checking yourself
Always confirm credentials and quotes with the business directly before hiring.
Look for consistent reviews across several named sources, not one polished profile.
Check any credential evidence, and that the business details independently check out.
Get a written quote and keep guarantee, insurance and payment terms in writing.
Want an extra legitimacy check? Run the Cowboy Checker on London Box Sash Windows Ltd before you contact them.
Run Cowboy Checker →Good to know
Common questions about London Box Sash Windows Ltd
Is London Box Sash Windows Ltd a legitimate business?
London Box Sash Windows Ltd has 141 independent public reviews, rated 5 out of 5. This is independent public evidence gathered from named public sources (no ads, no paid placement), not a guarantee of workmanship. If anything here is out of date, the business can request a correction.
What do customers say about London Box Sash Windows Ltd?
London Box Sash Windows Ltd has 141 public reviews, averaging 5 out of 5. The reviews section shows the aggregate rating, review volume, and review source information we hold.
How do I know London Box Sash Windows Ltd's reviews are genuine?
London Box Sash Windows Ltd's 141 public reviews come from a named public review source. MyTrustedTraders brings this public evidence together with no ads and no paid placement: we show the review source information and aggregate rating we hold rather than selling rankings, so you can weigh the evidence for yourself.
Is London Box Sash Windows Ltd qualified and accredited?
We hold 2 independently sourced credentials for London Box Sash Windows Ltd, including FENSA, Which? Trusted Trader. Each is attributed to the body that issued it in the credentials section. For example, FENSA is the competent-person scheme for replacement windows and doors, self-certifying they meet building regulations.
What does London Box Sash Windows Ltd specialise in?
London Box Sash Windows Ltd lists specialist services including Window consultants, Sash windows, Replacement window services and repairs, Timber windows, Double glazing installation, Joinery and carpentry. If your job is one of these, look for it in their listed services or ask them to confirm for your project.
When was London Box Sash Windows Ltd's website registered?
London Box Sash Windows Ltd's website has been online since 2010, according to the public domain registry. This dates the website, not necessarily when the business began trading.