Subdomain takeover · UK medium & large companies
What share of UK medium & large companies have a subdomain that is a takeover candidate?
5.56% of UK medium & large companies (95% CI 4.32–7.14%), measured across 1,025 companies on 2026-08-15.
Measured every Saturday since 2026-08-01 — 3 observations to date. Last measured 2026-08-15.
How this is measured
Tier 1. Subdomain enumeration (CT + DNS) plus dangling-target analysis, via one cached DomainAPI call per domain. Denominator: any, on a capped subset (heavy).
Passive measurement: a single DNS lookup, TLS handshake, or homepage GET per domain. Aggregate-only; no individual company is named. 95% Wilson confidence intervals. Population: national company registries (Companies House, Brreg, SIRENE), sampled by size band and resolved to email-active domains. Parked domains excluded. Snapshot: uk-companies-house-per600-seed20260728.
Licensed CC BY 4.0 — reuse with attribution to Quiet Failures. Download: JSON · CSV.
Check a specific domain against this control with the free Subdomain takeover scanner.
Why it matters
The archetypal quiet failure — a CNAME left pointing at a cancelled SaaS account. Nothing is broken, nothing alerts, and anyone who registers that account now serves content on your domain, with your name and often your cookies.
The same check, other segments
- the Philippines (domains)9.94%
- the UAE (domains)8.7%
- New Zealand (domains)7.36%
- Singapore (domains)6.75%
- Australia (domains)6.3%
- UK newly-formed (no accounts filed) companies6.25%
- Norway large companies6.01%
- Ireland (domains)5.73%
Show the remaining 65 segments
- Iceland (domains)5.56%
- Norway (domains)5.24%
- Hong Kong (domains)4.98%
- Canada (domains)4.65%
- UK companies4.43%
- Norway medium companies4.35%
- UK micro companies4.33%
- the UK (domains)4.06%
- India (domains)3.85%
- Norway companies3.81%
- Mexico (domains)3.77%
- Norway small companies3.72%
- Chile (domains)3.61%
- Malaysia (domains)3.59%
- South Africa (domains)3.46%
- the US (domains)3.36%
- France large companies3.26%
- Indonesia (domains)3.25%
- UK small companies3.14%
- UK dormant companies3.08%
- Romania (domains)2.97%
- Taiwan (domains)2.79%
- Denmark (domains)2.69%
- the EU (domains)2.68%
- Saudi Arabia (domains)2.64%
- Sweden (domains)2.62%
- France (domains)2.6%
- Peru (domains)2.6%
- global domains2.57%
- France small companies2.45%
- France companies2.14%
- Latvia (domains)2.07%
- France medium companies2%
- Norway micro companies1.88%
- Estonia (domains)1.79%
- Slovenia (domains)1.77%
- the Netherlands (domains)1.75%
- Thailand (domains)1.71%
- Finland (domains)1.5%
- Argentina (domains)1.44%
- Israel (domains)1.32%
- Vietnam (domains)1.21%
- Greece (domains)1.09%
- Italy (domains)1.09%
- Portugal (domains)1.07%
- Croatia (domains)1.03%
- Switzerland (domains)1.02%
- Belgium (domains)1.02%
- Bulgaria (domains)0.99%
- Hungary (domains)0.99%
- Austria (domains)0.99%
- France micro companies0.94%
- Czechia (domains)0.74%
- Luxembourg (domains)0.73%
- Japan (domains)0.69%
- Lithuania (domains)0.67%
- Slovakia (domains)0.67%
- Germany (domains)0.64%
- South Korea (domains)0.55%
- Russia (domains)0.54%
- Spain (domains)0.43%
- Brazil (domains)0.43%
- Poland (domains)0.43%
- Turkey (domains)0.37%
- Ukraine (domains)0%