Post Offices in Bismarck, North Dakota, United States SearchSearch SearchSearch View: Grid 1View: Grid 2View: Grid 3View: Grid 4View: Grid 5View: List Bismarck Post Office No Reviews Favorite Fax: (701) 221-6542Phone: (701) 221-6520Retail Hours Bismarck Downtown Post Office No Reviews Favorite Fax: (701) 255-6963Phone: (701) 221-6512Retail Hours