Cal. Civil Code § 2948.5

(a) A borrower shall not be required to pay interest on a principal obligation under a promissory note secured by a mortgage or deed of trust on real property improved with between one to four residential dwelling units for any period that meets any of the following requirements: (1) Is more than one day prior to the date that the loan proceeds are disbursed from escrow. (2) In the event of no escrow, if a request for recording is made in connection with the disbursement, is more than one day prior to the date the loan proceeds are disbursed to the borrower, to a third party on behalf of the borrower, or to the lender to satisfy an existing obligation of the borrower. (3) In all other circumstances where there is no escrow and no request for recording, is prior to the date funds are disbursed to the borrower, to a third party on behalf of the borrower, or to the lender to satisfy an existing obligation of the borrower. (b) Interest may commence to accrue on the business day immediately preceding the day of disbursement, for obligations described in paragraphs (1) and (2) of subdivision (a) if both of the following occur: (1) The borrower affirmatively requests, and the lender agrees, that the disbursement will occur on Monday, or a day immediately following a bank holiday. (2) The following information is disclosed to the borrower in writing: (A) the amount of additional per diem interest charged to facilitate disbursement on Monday or the day following a holiday, as the case may be, and (B) that it may be possible to avoid the additional per diem interest charge by disbursing the loan proceeds on a day immediately following a business day. This disclosure shall be provided to the borrower and acknowledged by the borrower by signing a copy of the disclosure document prior to placing funds in escrow. (c) This section does not apply to a loan that is subject to subdivision (c) of Section 10242 of the Business and Professions Code.