Post Offices in Elk River, Minnesota, United States SearchSearch SearchSearch View: Grid 1View: Grid 2View: Grid 3View: Grid 4View: Grid 5View: List Elk River Post Office No Reviews Favorite Fax: (763) 241-9983Phone: (763) 241-5297Retail Hours Elk River Carrier Annex Post Office No Reviews Favorite Fax: (763) 241-9983Phone: (763) 241-5297Retail Hours