Post Offices in Flagstaff, Arizona, United States SearchSearch SearchSearch View: Grid 1View: Grid 2View: Grid 3View: Grid 4View: Grid 5View: List Downtown Flagstaff Post Office No Reviews Favorite Fax: (928) 773-9480Phone: (928) 779-2371Retail Hours Flagstaff Post Office No Reviews Favorite Fax: (928) 714-9882Phone: (928) 714-9302Retail Hours