Rev. & Tax. Code, § 30206

The department shall give the person written notice of its determination. The notice shall be served in one of the following manners:

(a) By placing the notice in a sealed envelope, with postage paid, addressed to the person at their address as it appears in the records of the department. Service made pursuant to this subdivision shall be deemed complete at the time of deposit of the notice in the United States Post Office, or a mailbox, sub-post office, substation, or mail chute, or other facility regularly maintained or provided by the United States Postal Service, without extension of time for any reason.

(b) By personally delivering the notice to the person to be served. Service made pursuant to this subdivision shall be deemed complete at the time of such delivery. Personal service to a corporation may be made by delivery of a notice to any person designated in the Code of Civil Procedure to be served for the corporation with summons and complaint in a civil action.

(c) (1) By delivering the notice electronically via secure transmission when either of the following applies:

(A) The taxpayer requests the notice of determination to be sent electronically via secure transmission.

(B) The department has evidence that the taxpayer no longer receives mail at the address of record and has previously provided an address for electronic mail.

(2) Service provided pursuant to paragraph (1) shall be deemed complete at the time the department electronically transmits the notice via the taxpayer’s secure web portal, without extension of time for any reason.