Where does workers' comp x-date data come from?
For California's licensed contractors, the insurers: state law has each one report a contractor's policy number and coverage dates to the Contractors State License Board, whose free lists of contractors by classification show each policy's expiration date.
How a policy's dates reach CSLB's lists
| Step | What happens |
|---|---|
| The insurer files | An insurer licensed to write workers' compensation in California files a Certificate of Workers' Compensation Insurance with CSLB, online or by mail. It lists the license number, the policy number and the policy's effective and expiration dates. Source: CSLB's workers' compensation page. |
| The law requires it | The insurer reports the contractor's name, license number, policy number, the dates coverage is scheduled to start and lapse, and any cancellation date. Source: Business and Professions Code section 7125. |
| CSLB publishes it | CSLB's lists of contractors by classification, on its public data portal, give each license's coverage type, insurer, policy number and policy dates beside its address and county, and its master list has a separate workers' compensation file. |
A self-insured contractor holds a Certification of Self-Insurance instead of a policy. The Director of Industrial Relations issues and files it with CSLB, and CSLB's page says it must list the self-insured number and its own effective and expiration dates. A license with CSLB's exemption shows the coverage type Exempt, with no insurer, policy number or expiration date; which CSLB contractors do not have to carry workers' comp says who can file it. What an x-date is, and where the term comes from, is in the glossary entry for x-date.
CSLB's lists are free and need no account, and each list page says "There is no charge for this service." How to download them and filter them for policies expiring soon is on how to find California contractors whose workers' comp is expiring.
From those lists, which it downloads once a month, this site builds the weekly file of expiring policies, for one county or all of California. Each Monday's file keeps the licenses whose address is in California, or gives no state, of coverage type Workers' Compensation Insurance with no cancellation date recorded, whose policy expires in the 90 days from that Monday. It leaves out sole owners, and any license whose business name reads as a person's name unless CSLB lists it as a corporation or a limited liability company.