Cornerstone Construction CO, B General Building Contractor in Diamond Bar, CA
Cornerstone Construction CO operating as a sole owner holds California contractor license #427183, which is currently expired (lapsed Aug 31, 2026) and not valid to contract until it is renewed. First issued in 1982, the license has been on the CSLB roster for 44 years. It carries 2 CSLB classifications: B General Building Contractor and C-9 Drywall Contractor. Records show an active surety bond on file with Hudson Insurance Company and an exempt workers' compensation status (no employees on payroll). The business is based in Diamond Bar, in Los Angeles County, California.
- License Number
- 427183
- Issued
- Aug 26, 1982
- Status
- CLEAR
- Expires
- Aug 31, 2026
- Entity
- Sole Owner
- Surety
- Hudson Insurance Company
- Bond Number
- 30044171
- Effective
- Jan 1, 2023
- Status
- Active
- Coverage
- Exempt
- Carrier
- —
- Policy Number
- —
- Effective
- Aug 5, 2024
- Expires
- —
This contractor has a compliance issue in its public CSLB record:
- License expired
An automated summary of public CSLB data, not a credit score, rating, or endorsement. How we determine this
Is Cornerstone Construction CO licensed in California?
Cornerstone Construction CO previously held California Contractors State License Board license number 427183, but the license expired on August 31, 2026 and is not currently valid. It was first issued on August 26, 1982.
What does Cornerstone Construction CO specialize in?
Cornerstone Construction CO is licensed for 2 CSLB classifications: B General Building Contractor and C-9 Drywall Contractor.
Where is Cornerstone Construction CO headquartered?
Cornerstone Construction CO is headquartered at 1860 S Tintah Drive, Diamond Bar, CA 91765, in Los Angeles County, California.
Does Cornerstone Construction CO have an active surety bond on file with CSLB?
Yes. Cornerstone Construction CO has an active California contractor surety bond filed with Hudson Insurance Company.
Does Cornerstone Construction CO carry workers' compensation coverage?
Cornerstone Construction CO reports an exempt workers' compensation status, meaning the business has no employees on payroll.
How do I verify Cornerstone Construction CO's contractor license?
You can verify Cornerstone Construction CO's license directly with the California Contractors State License Board at https://www.cslb.ca.gov/OnlineServices/CheckLicenseII/LicenseDetail.aspx?LicNum=427183.
- License issuedAug 26, 1982
- Bond activeJan 1, 2023
- WC coverage startsAug 5, 2024
- License expiredAug 31, 2026
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