Cal. Business and Professions Code § 17538.35

(a) Unless otherwise permitted by law or contract, any provider of electronic mail service shall provide each customer with notice at least 30 days before permanently terminating the customer’s electronic mail address. (b) No contract for electronic mail service may permit termination of service without cause with less than a 30-day notice. For purposes of this subdivision, “termination of service without cause” means termination of service at the unfettered discretion of the service provider without regard to any conduct of the customer that violates the service provider’s terms of service or acceptable use policy. (c) For purposes of this section, “provider” shall mean the entity that controls the customer’s electronic mail address, and not the entity making the underlying network or access available to the provider or the customer. (d) No provider shall be liable under this section solely for a failure to comply with this section in the event a customer’s electronic mail address is permanently terminated due to the action or inaction of an entity making the underlying network or access available to the provider or the customer. (e) This section supersedes and preempts all rules, regulations, codes, statutes, or ordinances of all cities, counties, cities and counties, municipalities, and other local agencies regarding notice of electronic mail termination by providers of electronic mail service. (f) This section shall become inoperative on the date that a federal law or regulation is enacted that regulates notice requirements in the event of termination of electronic mail service.