Cornerstone Construction Co
Verified against CSLB on · View on CSLB
License details
- License number
- 427183
- Status
- Active
- Classifications
- B · General BuildingC-9 · Drywall
- Contractor bond
- $25,000
- Workers' comp
- Exempt
- License term on file
- August 26, 1982 – August 31, 2026
Business
- (909) 861 7978 (CSLB public record)
- 1860 S TINTAH DRIVE, Diamond Bar, CA 91765Los Angeles County
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Frequently asked questions
Is Cornerstone Construction Co licensed in California?
Yes. Cornerstone Construction Co holds an active California state contractor license (CSLB #427183), verified against the CSLB public record on June 17, 2026.
What is Cornerstone Construction Co's CSLB license number?
Cornerstone Construction Co's California contractor license number is 427183. You can verify it directly on the CSLB website: https://www.cslb.ca.gov/OnlineServices/CheckLicenseII/LicenseDetail.aspx?LicNum=427183
What kind of work is Cornerstone Construction Co licensed for?
Cornerstone Construction Co is classified under General Building (B) by the CSLB.
How do I verify Cornerstone Construction Co's license myself?
Look up license #427183 with the CSLB "Check a License" tool at https://www.cslb.ca.gov/OnlineServices/CheckLicenseII/LicenseDetail.aspx?LicNum=427183. This page reflects the CSLB public record as of June 17, 2026.
See an error in this record? Report incorrect information. Status reflects CSLB data as of the date shown above.