What's the difference between filing a complaint with the CSLB and filing a small claims lawsuit?

These serve genuinely different purposes, and understanding the distinction helps you use both effectively rather than picking one over the other. The Contractors State License Board, commonly called the CSLB, is the state agency that regulates contractor licenses themselves, it can discipline, suspend, or revoke a contractor's license, and it operates a mandatory arbitration program specifically designed for smaller disputes. What the CSLB generally does not do is write you a check directly for money you're owed.

A small claims lawsuit is the mechanism that actually produces an enforceable money judgment, a court order that you can then use collection tools, garnishment, bank levies, property liens, to enforce if the contractor doesn't pay voluntarily. These two paths aren't mutually exclusive, and in fact filing both simultaneously is standard practice: the CSLB complaint puts pressure on the contractor's license and creates an official record, while the small claims case is what actually gets you paid.