Companies using Customer.io in United Kingdom
As of 4 November 2026, 290 British companies show Customer.io: 267 on their website or in DNS records and 24 in their own job postings, led by London.
As of 4 November 2026 · refreshed daily · counts move as websites, DNS and career sites are re-read.
- Top city
- London · 53
- In both sources
- 1
- Most common size
- 11-50 employees
- Team that names it most
- Marketing & communications · 15 postings
- Top industry, posting companies
- Business & finance services
British companies on Customer.io
Every company in the country whose own postings name the tool; job boards and portals left out.
Open the sales or marketing leader at each one with a verified e-mail, or get new British Customer.io users every Monday.
Start free, no card. The first 20 are above; e-mails are verified at the mail server when you open them.
By city, company size, industry and team
Footprint tables first (website or DNS), then the companies whose postings name Customer.io.
| companies | share | |
|---|---|---|
| London | 53 | 20% |
| Bristol | 11 | 4% |
| Hoxton | 4 | 1% |
| Newington | 4 | 1% |
| Battersea | 3 | 1% |
| Edinburgh | 3 | 1% |
| Leeds | 3 | 1% |
| Market Harborough | 3 | 1% |
| Street | 3 | 1% |
| Aldgate East | 2 | 1% |
| companies | share | |
|---|---|---|
| Self-employed | 81 | 30% |
| 2-10 employees | 73 | 27% |
| 11-50 employees | 78 | 29% |
| 51-200 employees | 28 | 10% |
| 201-500 employees | 3 | 1% |
| 501-1000 employees | 1 | 0% |
| 1001-5000 employees | 1 | 0% |
| 10,001+ employees | 2 | 1% |
| companies | share | |
|---|---|---|
| London | 4 | 17% |
| Aldgate East | 1 | 4% |
| Camden | 1 | 4% |
| Jersey | 1 | 4% |
| Ladbroke Grove | 1 | 4% |
| Manchester | 1 | 4% |
| Nairobi | 1 | 4% |
| New York | 1 | 4% |
| Newington | 1 | 4% |
| Real | 1 | 4% |
| Swindon | 1 | 4% |
| White Notley | 1 | 4% |
| companies | share | |
|---|---|---|
| Self-employed | 2 | 8% |
| 2-10 employees | 3 | 13% |
| 11-50 employees | 7 | 29% |
| 51-200 employees | 6 | 25% |
| 201-500 employees | 4 | 17% |
| 501-1000 employees | 1 | 4% |
| 10,001+ employees | 1 | 4% |
| companies | share | |
|---|---|---|
| Business & finance services | 9 | 38% |
| Technology & software | 6 | 25% |
| Media & content | 4 | 17% |
| Health care | 3 | 13% |
| Consumer services & leisure | 1 | 4% |
| Property & construction | 1 | 4% |
| postings · companies | |
|---|---|
| Marketing & communications | 15 · 13 |
| Product, program & project management | 2 · 1 |
| Sales | 2 · 2 |
| Data & AI | 1 · 1 |
| Engineering (non-software) | 1 · 1 |
| IT operations & business systems | 1 · 1 |
Customer.io everywhere, and other tools here
All companies using Customer.io →
Companies hiring sales in United Kingdom →
customer engagement platforms compared →
Quote the sentence with the date and the link. The numbers change daily; the link always shows the current ones.
290 British companies show Customer.io: 267 carry it on their website or in their DNS records, 24 name it in their own job postings, 1 do both. (Breaknorm, 4 November 2026, https://breaknorm.co/tools/customer-io/united-kingdom)
Read from the source, not self-reported
Every number on this page can be traced to a page we crawled or a posting we read. Full methodology →
- Job postingsRead hourly from the applicant tracking systems behind British career sites. A tool counts when the employer's own text names it as the team's system.
- CountryFrom the company's own website: imprint, address, phone prefix and language, with a confidence score. Not the posting's location.
- Website and DNSScripts and embeds on the company's pages, plus SPF, DKIM, MX and CNAME records of its domain that point at the vendor.
- ExclusionsJob boards, portals and aggregators are kept out of company lists.
Customer.io in United Kingdom: questions
Is this every British company on Customer.io?
It is every British company whose website, DNS records or own job postings show it: 290 in total. Companies that use Customer.io without any public trace are not counted.
What does "United Kingdom" mean here?
The country of the company, from its own website (imprint, address, phone prefix, language), not where the posting is located. A German company hiring in Paris still counts as German.
How do I get the British list with e-mails?
Sign up, filter companies on Customer.io and United Kingdom, and open the people you want. Counting is free; the first 1,000 results are too.
Get this list your way
The same data as a search, over MCP and the API, as bulk files, or pushed to you as it changes.
Every British company on Customer.io,
with the person who owns it
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