Health Net Federal Services Customer Service Line (West Region) 1-844-866-WEST (1-844-866-9378) www.tricare-west.com. Monday through Friday, 5:00 a.m.-9:00 p.m. (Pacific time) Provider contracting and credentialing inquiries: Monday through Friday, 5:00 a.m.-6:00 p.m. (Pacific time) Provider locator services: 24 hours a day, seven days a week..