317-622-8970Search all companies →Companies in San Mateo, California
28,823 companies in San Mateo, California.
Find 28,823 companies in San Mateo, California. From manufacturers to industrial suppliers, each listing carries the firm's address, website, size, and NAICS/SIC codes. You can also browse nearby cities such as Los Angeles, San Francisco, San Diego.
Of the 28,594 with a known headcount, 97% employ 1-50 people and 52 employ more than 1,000. 97% of those reporting revenue are under $10M, while 43 report more than $1B.
These pages show the first 120 of 28,823 companies. Narrow the list with the filters above or open one of the related lists below to see the rest.
San Mateo, California companies by size and revenue
| Employees | Companies | Share |
|---|---|---|
| 1-50 | 27,768 | 97.1% |
| 51-200 | 562 | 2.0% |
| 201-1000 | 212 | 0.7% |
| 1001-5000 | 40 | 0.1% |
| 5001+ | 12 | 0.0% |
| Revenue | Companies | Share |
|---|---|---|
| Under $10M | 26,988 | 97.0% |
| $10M-$50M | 621 | 2.2% |
| $50M-$250M | 137 | 0.5% |
| $250M-$1B | 33 | 0.1% |
| $1B+ | 43 | 0.2% |
Share is of companies with a known value — 28,594 with headcount and 27,822 with revenue on file, as of Jul 17, 2026.
Frequently asked questions
How many companies are in San Mateo, California?
28,823 companies in the directory are located in San Mateo, California.
How many large companies are in San Mateo, California?
114 of the 28,823 companies in San Mateo, California employ more than 500 people, and 43 report over $1 billion in annual revenue. See the size and revenue breakdown above for the full distribution.
What size are most San Mateo, California companies?
Most are small and mid-sized businesses: the size and revenue tables above show the full spread, from under $10M up to $1B+, across the 27,822 companies with revenue on file.
What information is included for each company?
Every listing includes the company name, location, website, employee size, revenue range where available, and NAICS/SIC classification, with a link to the full profile.
Where does this directory come from?
Listings are compiled and maintained by Factur, a sales and marketing firm for B2B manufacturers. Any company can request an update or removal from its profile page.