Post Offices in Central Islip, New York, United States SearchSearch SearchSearch View: Grid 1View: Grid 2View: Grid 3View: Grid 4View: Grid 5View: List Central Islip Post Office No Reviews Favorite Fax: (631) 234-7429Phone: (631) 234-0547Retail Hours Federal Court House Post Office No Reviews Favorite Fax: (631) 715-0000Phone: (631) 715-0001Retail Hours