Post Offices in Marathon, Florida, United States SearchSearch SearchSearch View: Grid 1View: Grid 2View: Grid 3View: Grid 4View: Grid 5View: List Marathon Post Office No Reviews Favorite Fax: (305) 743-9431Phone: (305) 743-5238Retail Hours Marathon Shores Post Office No Reviews Favorite Fax: (305) 743-9431Phone: (305) 743-5238Retail Hours