California Code, Revenue and Taxation Code - RTC § 7284.1

(a) No license tax or fee levied by a charter or general law county, city and county, or city, or by a district or any other local agency, that is measured by the licensee's income or gross receipts, nor any flat business license tax or flat business license fee, shall apply to any minister, clergyman, Christian Science practitioner, rabbi, or priest of any religious organization that has been granted an exemption from federal income tax as an organization described in Section 501(c)(3) of the Internal Revenue Code 1 or a successor to that section.

(b) No charter or general law county, city and county, or city, nor any district or any other local agency, may impose any business license tax or business license fee on any nonprofit organization that is exempted from taxes by Section 23701d and is an organization described in Section 501(c)(3) of the Internal Revenue Code or the successor to that section.

(c) Nothing in this section shall prohibit a charter or general law county, city and county, or city, or district or any other local agency from imposing a fee to cover the costs of a program or service.