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California contractor license

Master Builders

Master Builders of San Francisco holds California license 850407 (A General Engineering, B General Building). The CSLB file dated Oct 26, 2026 lists it as active.1 It expires Nov 30, 2026.

Doing business as S F Twin Boys Corporation.

Active

  • License ends Nov 30, 2026 (35 days)

Master Builders, San Francisco

License
850407
Class
A General Engineering; B General Building
Expires
Nov 30, 2026
Bond
$25,000
Workers' comp
Insured to Jun 23, 2027

CSLB file dated Oct 26, 2026

What bond, insurance and workers' comp are on file?

Issued Nov 30, 2004.

Bond
$25,000American Contractors Indemnity Company, from Aug 25, 2023, continuous
Liability insurance
Not in the CSLB fileCheck with the board
Workers' comp
InsuredWesco Insurance Company, from Jun 23, 2026, to Jun 23, 2027

What work does this license cover?

What should you check before hiring?

What to ask before you hire

  1. Ask whether it has been renewed. Something on this license ends within 60 days. Check again before you pay a deposit.
  2. Get the license number in writing. The name on the license should match the name on your contract and invoice.
  3. Check the class covers the job. A license for one trade doesn't cover another. California license classes
  4. Ask for a certificate of insurance sent to you by the insurance agent, not handed over by the contractor. How to read a COI
  5. Ask who will be on site. If a crew works on your property, ask for proof of workers' comp. An exemption means the contractor told the CSLB it has no employees.
  6. Put it in a written contract: license number, price, start date and payment schedule. Check the license again on the day you sign.

If the license is lapsed

  1. Don't sign or pay a deposit until the CSLB shows the license active again.
  2. Ask the contractor why. For a bond or insurance lapse, ask for proof that the new bond or policy was filed with the CSLB, then check again.
  3. If work has started, hold further payments, keep the contract, receipts and photos, and file a complaint with Contractors State License Board (CSLB).
  4. Check another contractor. California license lookup

Sources

  1. CSLB License Master (cslb.ca.gov, Oct 26, 2026)
  2. Contractors State License Board (CSLB)