Post Offices in El Cajon, California, United States SearchSearch SearchSearch View: Grid 1View: Grid 2View: Grid 3View: Grid 4View: Grid 5View: List Bostonia Post Office No Reviews Favorite Fax: (619) 442-2824Phone: (619) 442-0257Retail Hours El Cajon Post Office No Reviews Favorite Fax: (619) 442-2811Phone: (619) 588-8665Retail Hours