California Code, Family Code - FAM § 4508

(a) This section does not apply to any child support obligor who is subject to an earnings assignment order pursuant to Chapter 8 (commencing with Section 5200).

(b) Except as provided in subdivision (a), every order or judgment to pay child support may require a child support obligor to designate an account for the purpose of paying the child support obligation by electronic funds transfer, as defined in subdivision (a) of Section 6479.5 of the Revenue and Taxation Code. The order or judgment may require the obligor to deposit funds in an interest-bearing account with a state or federally chartered commercial bank, a savings and loan association, or in shares of a federally insured credit union doing business in this state, and shall require the obligor to maintain funds in the account sufficient to pay the monthly child support obligation. The court may order that each payment be electronically transferred to either the obligee's account or the local child support agency account. The obligor shall be required to notify the obligee if the depository institution or the account number is changed. No interest shall accrue on any amount subject to electronic funds transfer as long as funds are maintained in the account that are sufficient to pay the monthly child support obligation.