CALIFORNIA CODE OF CIVIL PROCEDURE
SERVICE OF SUMMONS
Service of Summons Outside California
C.C.P. Section 415.40
A summons may be served on a person outside this state in any manner provided by this article or by sending a copy of the summons and of the complaint to the person to be served by first-class mail, postage prepaid, requiring a return receipt.
Service of a summons by this form of mail is deemed complete on the 10th day after such mailing.