United States Government--post Office 305 Main St Buffalo, ND 58011 Phone : (701) 633-5298 Business Category Government Offices-Federal Post Offices Government Offices & Public Schools Post Office - Buffalo 305 Main St Buffalo, ND 58011 Phone : (701) 633-5298 Business Category Post Offices Government Offices & Public Schools Toll-Free           (800) ASK-USPS Fax           (605) 357-4906