California Code, Vehicle Code - VEH § 23305

(a) An issuing agency shall allow a driver of a rental vehicle to register the rental vehicle to a transponder or other electronic toll payment device account with the issuing agency prior to traveling on the issuing agency's toll facility for the purpose of paying all tolls with a credit or debit card. The issuing agency may require the use of a transponder for this purpose.

(b) The public entities operating or planning to implement a toll facility in this state shall cooperate to publish an internet website at which the public and rental car agencies can view and download, or that provides direct links to, information about how to open an account or acquire a transponder or other electronic toll payment device, for use of each issuing agency's toll facility. The rental car agency shall provide the customer with a written or electronic notice, including the electronic link for the internet website. The notice shall be separate from the rental contract and, if an electronic notice, emailed to the rental customer.

(c) This section shall become operative on July 1, 2024.