Post Office - South Colby 9650 Se Southworth Dr South Colby, WA 98384 Phone : (360) 871-0311 Post Office - South Colby Business Category Post Offices Toll-Free           (800) ASK-USPS Fax           (360) 871-2128 United States Government--postal Service, South Colby 9654 Se Southworth Dr Port Orchard, WA 98366 Phone : (360) 871-0311 United States Government--postal Service, South Colby Business Category Government Offices-Federal Government Offices & Public Schools