California Code, Business and Professions Code - BPC § 3631

(a) An applicant for licensure shall pass the Naturopathic Physicians Licensing Examination (NPLEX) or an equivalent examination approved by the North American Board of Naturopathic Examiners.

(b) In the absence of an examination approved by the North American Board of Naturopathic Examiners, the board may administer a substantially equivalent examination.

(c) The board may additionally require an applicant to pass any NPLEX elective examinations relevant to a licensee's scope of practice in California.