How to find UK companies by the technology they use
Technographic targeting — every UK company running WordPress, or Shopify, or a Meta pixel — is one of the sharpest filters in B2B, and it's awkward to build for one reason: the two datasets you need have no key in common. Companies House knows the company number, the SIC code and the incorporation date, but holds no website. Technology indexes know the domain and its stack, but not who legally owns it. This page is the honest route across that gap, what the detection genuinely sees, and a real measurement from our own scan rather than a claim about one.
The two halves, and why neither is enough alone
| Route | What you get | Where it stops |
|---|---|---|
| Companies House (search, API or bulk download) | Every live UK company with SIC codes, incorporation date, accounts category and registered address — free | No website field of any kind, so no technology, and no way to tell a trading business from a dormant shell |
| Global technology indexes (BuiltWith, Wappalyzer and similar) | Domains grouped by the stack they run, across the whole web, refreshed continuously | Domain-first, not company-first: no company number, SIC code or register filters, so the join back to the UK register is yours to do by hand |
| Do it yourself (script the register, then fetch each site) | Full control, and the only route that puts a company number and a tech column in the same row for free | Resolving companies to their real websites is the hard part, not the fetching — most of the cost is here, and mis-resolution poisons the whole list |
The register data underneath all three routes is the same official Companies House open data. What differs is who does the resolution and enrichment work, and how much of the result you can trust.
Resolving companies to websites is where lists go wrong
Guessing a domain from a company name is fast and quietly disastrous: the same trading name is used by unrelated companies, dissolved shells keep parked domains, and holding companies never match their brands. We grade every website match against the register entry rather than asserting it — confirmed when the site itself evidences the registered company, probable on strong corroboration, unverified when it's a plausible candidate only, and mismatch when the site clearly belongs to someone else. That grade ships in the file, so you can drop everything below your own bar instead of trusting ours. A technology column on top of an ungraded domain guess is confident nonsense.
What we actually measured
Rather than assert coverage, here is a run. The cohort is 231,476 UK digital, IT and marketing agencies pulled from the live register (SIC 62012, 62020, 70210, 73110, 73120 and 74100). A stratified 1,000-company sample went through the full pipeline — register enrich, website discovery, then homepage signal scan — completed 6 July 2026. Of those 1000 companies, 434 had a candidate website (207 of them graded confirmed or probable against the register entry), and 413 homepages were successfully fetched — 10 were declined by the site's robots.txt, which we obey, and 11 failed to fetch. Everything below is a share of those 413 fetched homepages.
| Detected platform | Sites | Share of fetched |
|---|---|---|
| Custom / no detectable CMS | 190 | 46.0% |
| WordPress | 159 | 38.5% |
| Wix | 26 | 6.3% |
| Squarespace | 25 | 6.1% |
| Webflow | 9 | 2.2% |
| Shopify | 4 | 1.0% |
| Other signals | Sites | Share of fetched |
|---|---|---|
| Google Analytics 4 tag present | 97 | 23.5% |
| At least one e-commerce marker (cart, checkout, WooCommerce…) | 101 | 24.5% |
| Careers or vacancies page live | 70 | 16.9% |
| Meta (Facebook) pixel present | 8 | 1.9% |
Computed from the scan output, not typed in by hand. These figures describe UK agency-sector companies specifically — they are not a statement about UK companies in general, and we won't quote them as one.
Three things that breakdown should tell you
First, the register is mostly websiteless: even in a digital-services cohort, over half the companies sampled had no findable site at all. Any technology filter is therefore a filter on a minority of the register, and a vendor quoting sector-wide totals without that caveat is quoting the wrong denominator. Second, “no detectable CMS” is the largest group — a hand-built or headless front end is the norm at the top of this sector, so a WordPress-only filter silently excludes exactly the companies most likely to have budget. Third, tracking tags are rarer than people assume: a GA4 tag on roughly a quarter of live sites is a genuinely selective signal, not a rounding error — which makes it useful as a proxy for “this site is actively managed”.
Want a technology-filtered cut of the UK register? Give us the technology filter (platform, analytics, e-commerce or hiring signals) plus the register filters — SIC codes or industry, region, company age, size band. You get one clean, de-duplicated CSV with each website graded against its Companies House record and every signal timestamped — within 48 hours, fixed price from £149, quoted before you pay.
What we deliberately don't do
We don't sell named individuals, email addresses or direct dials — company-level data only, as a deliberate GDPR stance rather than a roadmap gap. We don't scrape sites that decline in robots.txt, and those companies are reported as declined rather than quietly dropped. And we don't claim continuous monitoring: each run is a dated snapshot. If a global, always-on technology index across every domain on the web is what you need, a dedicated tech index is genuinely the better tool and worth its price — come to us when the join to the UK register, and the register fields alongside it, is the part that matters.
Want to see the output before commissioning a run? UK Digital & Marketing Agencies — Verified + Buying Signals. 1,596 established UK agencies, every row with a website verified against the Companies House record and at least one live buying signal. £99 one-off, with a free 50-row sample so you can check the quality first.
Frequently asked questions
Can you get a list of UK companies by the technology their website uses?
Yes, but not from the company register — Companies House holds no website field at all, let alone a technology one. It has to be built in two steps: resolve each company on the register to its real website, then read that website's homepage for platform and tracking markers. Global technology indexes like BuiltWith and Wappalyzer do the second step across the whole web, and do it well; what they don't carry is the company number, SIC code, incorporation date or accounts band, so joining their output back to the UK register is manual work you inherit. Firmfeed runs both steps against the register itself, so the technology column and the company-law fields arrive in one row.
How accurate is homepage technology detection?
Honest answer: good for mainstream platforms, imperfect at the edges. We read the homepage HTML and response headers for platform fingerprints — Shopify CDN and theme markers, WordPress paths, Wix, Squarespace and Webflow generators — plus GA4 and Meta pixel tags and e-commerce markers like carts and checkouts. That catches standard installs reliably. It will miss a headless build that serves a custom front end over a hidden platform, a site behind an aggressive edge cache that strips fingerprints, and anything gated behind a consent wall before scripts load. In our own run, 190 of 413 fetched sites showed no detectable CMS at all, and some of those are certainly running something we couldn't see from the homepage. We report what we detected, never what we inferred.
Is a technology list point-in-time or ongoing?
Point-in-time. Every signal row carries the timestamp it was checked, because sites get replatformed, tags get removed and companies stop trading. A list bought in January is a January snapshot, and anyone selling you a technology list as an evergreen asset is selling you decay. If you need it kept current, ask for a refresh cadence when you scope the order and we'll quote it — the same run, repeated, not a subscription you have to remember to cancel.
Do you cover the whole UK register or just some sectors?
The scan runs against whatever cut of the live register you brief — any SIC codes, region, company age or size band. What is already measured and published on this page is one cohort: 231,476 UK digital, IT and marketing agencies, of which a 1,000-company stratified sample has been through the full pipeline. Numbers from that sample describe agencies, not UK companies in general, and we don't quote them as though they did. For a different sector we'd run the same pipeline on that sector rather than extrapolate.
What does a technology-filtered list cost?
Fixed prices from £149, quoted before you pay, delivered as clean CSV within 48 hours of payment. Tell us the technology filter you want (say, WordPress sites among UK marketing agencies incorporated in the last five years) plus the register filters, and the quote comes back before any money moves. If the filter can't be built honestly from public sources — a technology that leaves no public fingerprint, for instance — we say so at scoping rather than after you've paid. Company-level data only: no scraped personal contacts, by design.
Related: how to get a list by SIC code or industry, how to add websites to Companies House data, or the full UK company data providers guide.