- 28 United States History Revolution, 1775-1783
- 6 United States Hotel
- 1 United States Life Savings Department
- 22 United States Military Academy
- 1 United States Mutual Fire Insurance Co. (Firm)
- 4 United States Naval Shipyard
- 13 United States Navy (USN)
- 13 United States Post Office
- 1 United States Quartermaster
- 11 United States Sanitary Commission
- 1 United States Sewing Machine Co.
- 1 United States, Southern
- 1 United Tanning Co.
- 1 Unity
- 3 Unity Street
- 1 Universal City, California
- 2 Universal Composition Co. (paints, varnishes, etc.)
- 1 Universalist Church of the Messiah
- 9 Universities
- 80 Universities & colleges
- 2 Universities (institutions)
- 1 University Avenue
- 109 University Of Pennsylvania
- 1 University of Pennsylvania Lane
- 1 University of Pennsylvania. Architectural Society
- 6 University of Pennsylvania. College Hall
- 1 University of Philadelphia
- 11 University of the Arts (Philadelphia, Pa.)
- 2 Unon Tavern
- 1 Unrest
- 3 'Unwan
- 3 Upholstered seats
- 1 Upholstering
- 3 Upholstery
- 12 Upland, Pennsylvania
- 1 Upper Chichester Township, Pennsylvania
- 42 Upper Darby, Pennsylvania
- 1 Upper Dublin Township, Pennsylvania
- 2 Upper Falls, Yellowstone National Park
- 4 Upper Merion Township, Pennsylvania
