| A-a Lock & Alarm INC | James Bruce Mac Lachlan | — | (650) 326 9020 | Alarm and generators | Menlo Park · San Mateo County | — | — |
| Bay City Security Specialist | Bay City Security Specialist | service@baycitysecurityspecialist.com | (650) 274 9725 | Alarm and generators | San Bruno · San Mateo County | — | — |
| D C Lock & Security INC | Michael Paul Sink | — | (650) 992 2451 | Alarm and generators | Daly City · San Mateo County | — | — |
| Fire Alarm Services | Fire Alarm Services | info@firealarmsystemservices.com | (650) 815-7066 | Alarm and generators | San Mateo · San Mateo County | — | — |
| Fire Watch Guard Services San Mateo | Fire Watch Guard Services San Mateo | — | (650) 706-4887 | Alarm and generators | San Mateo · San Mateo County | — | — |
| North Cal Security | North Cal Security | — | (650) 684 7372 | Alarm and generators | South San Francisco · San Mateo County | — | — |
| Qikfox Cybersecurity Systems Inc. | Qikfox Cybersecurity Systems Inc. | hello@qikfox.com | (855) 303-1168 | Alarm and generators | San Mateo · San Mateo County | — | — |
| San Mateo Security Services | San Mateo Security Services | — | (650) 329-1048 | Alarm and generators | San Mateo · San Mateo County | — | — |
| Security 101 - San Mateo | Security 101 - San Mateo | — | (650) 249-3315 | Alarm and generators | San Mateo · San Mateo County | — | — |
| Signature Fire Protection San Mateo | Signature Fire Protection San Mateo | — | (650) 910-3984 | Alarm and generators | San Mateo · San Mateo County | — | — |
| Vantage Security Guards San Mateo | Vantage Security Guards San Mateo | — | (650) 870-0942 | Alarm and generators | San Mateo · San Mateo County | — | — |
| Verkada | Verkada | — | (650) 514-2500 | Alarm and generators | San Mateo · San Mateo County | — | — |
| West Coast Security Inc. | West Coast Security Inc. | info@wcsecurity.com | (800) 421-2585 | Alarm and generators | San Carlos · San Mateo County | — | — |