Mas Service, C-20 HVAC Contractor in Antioch, CA
Mas Service operating as a corporation holds an active California contractor license (CSLB #498289), valid through Jun 30, 2026. First issued in 1986, the license has been on the CSLB roster for 40 years. It carries 2 CSLB classifications: C-20 HVAC Contractor and C-38 Refrigeration Contractor. Records show an active surety bond on file with Ohio Casualty Insurance Company (the) and active workers' compensation coverage from Insurance Company of the West. The business is based in Antioch, in Contra Costa County, California.
- License Number
- 498289
- Issued
- Sep 15, 1986
- Status
- CLEAR
- Expires
- Jun 30, 2026
- Entity
- Corporation
- Surety
- Ohio Casualty Insurance Company (the)
- Bond Number
- 792706C
- Effective
- Jan 1, 2023
- Status
- Active
- Coverage
- Workers' Compensation Insurance
- Carrier
- Insurance Company of the West
- Policy Number
- WPL508874000
- Effective
- Mar 3, 2026
- Expires
- Mar 3, 2027
This contractor warrants a closer look before contracting:
- License expires in 2 days
An automated summary of public CSLB data, not a credit score, rating, or endorsement. How we determine this
Is Mas Service licensed in California?
Yes. Mas Service holds California Contractors State License Board license number 498289, which is active and in good standing. The license was first issued on September 15, 1986. It is valid through June 30, 2026.
What does Mas Service specialize in?
Mas Service is licensed for 2 CSLB classifications: C-20 HVAC Contractor and C-38 Refrigeration Contractor.
Where is Mas Service headquartered?
Mas Service is headquartered at 5083 Lone Tree Way, Antioch, CA 94531, in Contra Costa County, California.
Does Mas Service have an active surety bond on file with CSLB?
Yes. Mas Service has an active California contractor surety bond filed with Ohio Casualty Insurance Company (the).
Does Mas Service carry workers' compensation coverage?
Yes. Mas Service carries active workers' compensation coverage through Insurance Company of the West.
How do I verify Mas Service's contractor license?
You can verify Mas Service's license directly with the California Contractors State License Board at https://www.cslb.ca.gov/OnlineServices/CheckLicenseII/LicenseDetail.aspx?LicNum=498289.
- License issuedSep 15, 1986
- Bond activeJan 1, 2023
- WC coverage startsMar 3, 2026
- License expiresJun 30, 2026
- WC expiresMar 3, 2027
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