Post office in Mad River Near Me Find Post office in Mad River near me. United States Postal Service Establishment Finance Post office 2515B State Highway 36, Mad River, CA 95552 +1 800-275-8777 CALIFORNIA-PAGES.COM Mad River Post office Categories of companies in Mad River, California All categories Campground Church Establishment Finance Fire station Food Furniture store General contractor Health Home goods store Lodging Museum Park Place of worship Post office School Supermarket