Companies using Customer.io in United States
As of 5 November 2026, 2,137 US companies show Customer.io: 2,004 on their website or in DNS records and 150 in their own job postings, led by San Francisco.
As of 5 November 2026 · refreshed daily · counts move as websites, DNS and career sites are re-read.
- Top city
- San Francisco · 69
- In both sources
- 17
- Most common size
- 11-50 employees
- Team that names it most
- Marketing & communications · 66 postings
- Top industry, posting companies
- Technology & software
US companies on Customer.io
Companies with 51+ employees and high-confidence evidence in their own postings; job boards and portals left out.
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By city, company size, industry and team
Footprint tables first (website or DNS), then the companies whose postings name Customer.io.
| companies | share | |
|---|---|---|
| San Francisco | 69 | 3% |
| New York | 52 | 3% |
| Austin | 25 | 1% |
| Miami | 15 | 1% |
| Chicago | 13 | 1% |
| Atlanta | 12 | 1% |
| companies | share | |
|---|---|---|
| Self-employed | 785 | 39% |
| 2-10 employees | 432 | 22% |
| 11-50 employees | 544 | 27% |
| 51-200 employees | 169 | 8% |
| 201-500 employees | 47 | 2% |
| 501-1000 employees | 21 | 1% |
| 1001-5000 employees | 5 | 0% |
| 10,001+ employees | 1 | 0% |
| companies | share | |
|---|---|---|
| San Francisco | 15 | 10% |
| New York | 10 | 7% |
| Austin | 5 | 3% |
| Denver | 3 | 2% |
| Atlanta | 2 | 1% |
| Chicago | 2 | 1% |
| Los Angeles | 2 | 1% |
| Mountain View | 2 | 1% |
| Washington | 2 | 1% |
| Xonacatlán | 2 | 1% |
| Amsterdam | 1 | 1% |
| companies | share | |
|---|---|---|
| Self-employed | 7 | 5% |
| 2-10 employees | 19 | 13% |
| 11-50 employees | 44 | 29% |
| 51-200 employees | 33 | 22% |
| 201-500 employees | 26 | 17% |
| 501-1000 employees | 12 | 8% |
| 1001-5000 employees | 9 | 6% |
| companies | share | |
|---|---|---|
| Technology & software | 82 | 55% |
| Business & finance services | 22 | 15% |
| Health care | 19 | 13% |
| Consumer services & leisure | 7 | 5% |
| Commerce & trade | 6 | 4% |
| Media & content | 6 | 4% |
| Manufacturing & industry | 5 | 3% |
| Public, community & associations | 1 | 1% |
| Hospitality & travel | 1 | 1% |
| Property & construction | 1 | 1% |
| postings · companies | |
|---|---|
| Marketing & communications | 66 · 54 |
| Product, program & project management | 6 · 5 |
| Software engineering | 6 · 5 |
| Customer service & success | 4 · 4 |
| Data & AI | 4 · 3 |
| Sales | 4 · 3 |
| Business development & strategy | 1 · 1 |
| Design & UX | 1 · 1 |
| Manufacturing and production | 1 · 1 |
Customer.io everywhere, and other tools here
All companies using Customer.io →
Companies hiring sales in United States →
customer engagement platforms compared →
Quote the sentence with the date and the link. The numbers change daily; the link always shows the current ones.
2,137 US companies show Customer.io: 2,004 carry it on their website or in their DNS records, 150 name it in their own job postings, 17 do both. (Breaknorm, 5 November 2026, https://breaknorm.co/tools/customer-io/united-states)
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 US 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 States: questions
Is this every US company on Customer.io?
It is every US company whose website, DNS records or own job postings show it: 2,137 in total. Companies that use Customer.io without any public trace are not counted.
What does "United States" 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 US list with e-mails?
Sign up, filter companies on Customer.io and United States, and open the people you want. Counting is free; the first 1,000 results are too.
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The same data as a search, over MCP and the API, as bulk files, or pushed to you as it changes.
Every US company on Customer.io,
with the person who owns it
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