JB MECHANICAL INC DBA MAS SERVICE
HVAC Contractor license 498289 issued by the California Contractors State License Board. Status shown as of August 17, 2026.
This license is active. It is valid through June 30, 2028, 683 days from today, according to the most recent CSLB public file.
| License holder | JB MECHANICAL INC DBA MAS SERVICE |
|---|---|
| Business name | JB MECHANICAL INC DBA MAS SERVICE |
| License type | HVAC Contractor |
| License number | 498289 |
| Status today | Active |
| Expiration date | June 30, 2028 |
| City | Antioch |
| County of record | Contra Costa |
| Phone on file | (888) 314 0451 |
| Classifications | C20, C38 |
| Board status | CLEAR |
| Contractor bond | $25,000 |
| Issuing authority | California Contractors State License Board |
| First seen in public file | August 17, 2026 |
| Last confirmed | August 17, 2026 |
How to confirm this yourself
This page reproduces the CSLB public license file, which the agency republishes daily. Before you hire anyone, confirm the record at the source and ask the contractor for proof of insurance separately, since licensing and insurance are not the same thing and the state file does not cover insurance.
Verify at CSLB → File a complaint
There are 245 licensed HVAC contractors on record in Contra Costa County. Compare them all →