Post Offices in Lynnfield, Massachusetts, United States SearchSearch SearchSearch View: Grid 1View: Grid 2View: Grid 3View: Grid 4View: Grid 5View: List Lynnfield Post Office No Reviews Favorite Fax: (781) 334-0870Phone: (781) 334-3932Retail Hours South Lynnfield Post Office No Reviews Favorite Fax: (781) 598-1501Phone: (781) 598-4205Retail Hours