Duff & Sons Inc

Mammoth Lakes · Mono County · CA

VERIFIED

Bestopedia verdict

82 / 100 Bestopedia Trust Score

California’s contractor board lists Duff & Sons Inc in CLEAR standing. A contractor bond is on file, and workers’ compensation coverage is current.

License standing
30 / 30
Years licensed
6.4 / 20
Contractor bond
20 / 20
Workers' comp
16 / 20
Business structure
10 / 10

How the Trust Score is calculated →

The verified record

CSLB license
#1063434 verify on CSLB ↗
Classifications
B, C-10
Years licensed
6.4 years since 02/18/2020
Contractor bond
$25,000 AMERICAN CONTRACTORS INDEMNITY COMPANY
Workers’ comp
Current
Business type
Corporation
Qualifying principal
Grant Kelly Ii Duff
Address of record
P O Box 1387, Mammoth Lakes, CA 93546

Frequently Asked Questions

Is Duff & Sons Inc a licensed Electrical contractor in California?

Yes. Duff & Sons Inc holds California CSLB contractor license #1063434 with a C-10 (Electrical) classification. Current CSLB status: CLEAR.

What work is Duff & Sons Inc licensed to perform?

License #1063434 carries C-10 (Electrical), plus additional classifications: B.

Is Duff & Sons Inc bonded?

Yes. Duff & Sons Inc carries contractor's bond #100740955 for $25,000 through AMERICAN CONTRACTORS INDEMNITY COMPANY.

Does Duff & Sons Inc carry workers' compensation insurance?

Workers' compensation status on file: Exempt.

How long has Duff & Sons Inc held its contractor license?

License #1063434 was originally issued on 02/18/2020, approximately 6 years ago (as of July 2026).

Where is Duff & Sons Inc located?

Duff & Sons Inc is based in Mammoth Lakes, Mono County, CA 93546.