C-51 — Structural Steel Contractor
Compliance obligations for California C-51 (Structural Steel Contractor) contractors. Keep every deadline tracked to stay licensed and avoid penalties.
Compliance Obligations
| Obligation | Agency | Cycle | Fee |
|---|---|---|---|
| CSLB Contractor License Renewal | Contractors State License Board (CSLB) | 2 years | $450 |
| Contractor License Bond | Contractors State License Board (CSLB) | continuous | $25,000 |
| Bond of Qualifying Individual | Contractors State License Board (CSLB) | continuous | $25,000 |
| LLC Employee/Worker Bond | Contractors State License Board (CSLB) | continuous | $100,000 |
| Workers' Compensation Insurance | Department of Industrial Relations (DIR) | annual | Varies by classification and payroll |
Workers' Compensation
Workers' comp is required for C-51 contractors.
Mandatory date: 2028-01-01 (Phase 2). Contractors with employees must carry workers' compensation insurance at all times.
Scope of Work
View full statutory scope of work ▼
A structural steel contractor fabricates and erects structural steel shapes and plates, of any profile, perimeter or cross-section, that are or may be used as structural members for buildings and structures, including the riveting, welding, rigging and metal roofing systems necessary to perform this work.
Track your C-51 deadlines automatically.
PermitCal pre-loads every compliance deadline for C-51 (Structural Steel Contractor) contractors. Join the waitlist.
City Business Licenses
In addition to state requirements, you may need a city business license.
Renewal: January 1 (calendar year)
Renewal: May 31 (registration renewal); March 1 (annual business tax return)
Renewal: January 1 (calendar year)
Renewal: December 31 (calendar year)
Renewal: March 1 (annual)
Renewal: January 31 (calendar year, certificate expires December 31)
Renewal: March 1 (calendar year)
Renewal: Anniversary of license issue date (annual)
Renewal: July 31 (fiscal year ending June 30)
Renewal: Anniversary of issue date (rolling annual renewal)
Renewal: January 31 (calendar year, renewal notices mailed in November)
Renewal: April 1 (fiscal year April 1 - March 31)
Renewal: Anniversary-based (rolling annual expiration)
Renewal: Annual (due first day of month after expiration) or quarterly (Jan 1, Apr 1, Jul 1, Oct 1)
Renewal: June 30 (fiscal year July 1 - June 30, renewal due July 31)