Plonowski Architects + Builders, B General Building Contractor in Mill Valley, CA
Plonowski Architects + Builders operating as a sole owner holds an active California contractor license (CSLB #649916), valid through Jul 31, 2026. First issued in 1992, the license has been on the CSLB roster for 34 years. It carries a single CSLB classification: B — General Building Contractor. Records show an active surety bond on file with Business Alliance Insurance Company and a previously-filed workers' compensation policy with Transportation Insurance Company that is no longer active. The business is based in Mill Valley, in Marin County, California.
- License Number
- 649916
- Issued
- Jul 14, 1992
- Status
- CLEAR
- Expires
- Jul 31, 2026
- Entity
- Sole Owner
- Surety
- Business Alliance Insurance Company
- Bond Number
- G141223297765
- Effective
- Feb 4, 2025
- Status
- Active
- Coverage
- Workers' Compensation Insurance
- Carrier
- Transportation Insurance Company
- Policy Number
- 7039131404
- Effective
- Dec 21, 2025
- Expires
- Dec 21, 2026
- Cancelled
- Apr 22, 2026
This contractor has a compliance issue in its public CSLB record:
- Workers' comp cancelled
An automated summary of public CSLB data, not a credit score, rating, or endorsement. How we determine this
Is Plonowski Architects + Builders licensed in California?
Yes. Plonowski Architects + Builders holds California Contractors State License Board license number 649916, which is active and in good standing. The license was first issued on July 14, 1992. It is valid through July 31, 2026.
What does Plonowski Architects + Builders specialize in?
Plonowski Architects + Builders is licensed for one CSLB classification: B General Building Contractor.
Where is Plonowski Architects + Builders headquartered?
Plonowski Architects + Builders is headquartered at 23 Dorset Lane, Mill Valley, CA 94941, in Marin County, California.
Does Plonowski Architects + Builders have an active surety bond on file with CSLB?
Yes. Plonowski Architects + Builders has an active California contractor surety bond filed with Business Alliance Insurance Company.
Does Plonowski Architects + Builders carry workers' compensation coverage?
Plonowski Architects + Builders has a previously-filed workers' compensation policy with Transportation Insurance Company that is no longer active.
How do I verify Plonowski Architects + Builders's contractor license?
You can verify Plonowski Architects + Builders's license directly with the California Contractors State License Board at https://www.cslb.ca.gov/OnlineServices/CheckLicenseII/LicenseDetail.aspx?LicNum=649916.
- License issuedJul 14, 1992
- Bond activeFeb 4, 2025
- WC coverage startsDec 21, 2025
- WC cancelledApr 22, 2026
- License expiresJul 31, 2026
- WC expiresDec 21, 2026
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