Cal. Rev. & Tax. Code § 18671

(a) Subject to the limitations in subdivisions (b) and (c), the Franchise Tax Board, may, by notice, served personally, by first-class mail, or by electronic transmission or other electronic technology, require any person, officer, department of the state, or political subdivision or agency of the state including the Regents of the University of California, a city organized under a freeholder’s charter, or a political body not a subdivision or agency of the state, to withhold the amount of any tax, interest, or penalties due from a taxpayer, or the amount due from an employer or person who has failed to withhold and transmit amounts due pursuant to this article, from any payments due the taxpayer, employer, or person and from any payments becoming due the taxpayer, employer, or person after receipt of the notice. The amounts withheld shall be transmitted to the Franchise Tax Board at those times as it may designate.
(b) The effect of a levy made pursuant to subdivision (a) shall be continuous from the date the notice is received until the amount due stated on the notice has been withheld, until the notice has been withdrawn, or until one year after the date the notice is received, whichever occurs first.
(c) The amount required to be withheld pursuant to a notice issued under subdivision (a) is the lesser of the amount due stated on the notice, or either of the following:
1. (1) If the taxpayer, employer, or person is not a natural person, 100 percent of the amount of each payment due or becoming due the taxpayer, employer, or person during the period the levy is in effect as provided in subdivision (b).
2. (2) If the taxpayer, employer, or person is a natural person, 25 percent of the amount of each payment due or becoming due the taxpayer, employer, or person during the period the levy is in effect as provided in subdivision (b).
(d) Any notice or document required to be served or provided in connection with the notice to withhold described in subdivision (a) may be served personally, by first-class mail, or by electronic transmission or other electronic technology.
(e) Upon consent, the Franchise Tax Board may provide service by electronic transmission or other electronic technology under this section.
(f) For purposes of this section, the term “payments” does not include earnings as defined in subdivision (a) of Section 706.011 of the Code of Civil Procedure or funds in a deposit account as defined in paragraph (29) of subdivision (a) of Section 9102 of the Commercial Code. The term “payments” does include any of the following:
1. (1) Payments due for services of independent contractors, dividends, rents, royalties, residuals, patent rights, or mineral or other natural resource rights.
2. (2) Payments or credits due or becoming due as a result of written or oral contracts for services or sales whether denominated as wages, salary, commission, bonus, or otherwise.
3. (3) Any other payments or credits due or becoming due periodically as a result of an enforceable obligation to the taxpayer, employer, or person.
(g) The amendments made to this section by the act adding this subdivision shall apply to notices served or provided on or after the effective date of the act.