| PEN | Pacific Exchange Network 
| Others |
| PEN | Parent Education Network
| Others |
| PEN | Parent Engagement Network
| Others |
| PEN | Parenteral and Enteral Nutrition
| Others |
| PEN | Parents Education Network
| Others |
| PEN | Parity Enable
| Others |
| PEN | Pasadena Education Network
| Others |
| PEN | Pay, Educate, and Nourish
| Others |
| PEN | PCB Elimination Network
| Others |
| PEN | PCBs Elimination Network
| Others |
| PEN | Penang International Airport
| Others |
| PEN | Penang, Malaysia
| Others |
| PEN | PENicillin
| Others |
| PEN | Penitentiary Emergency Network
| Others |
| PEN | Pennsylvania Education Network
| Others |
| PEN | People Eat Nutts
| Others |
| PEN | Periodic Electronic Newsletter
| Others |
| PEN | Permanent Employee Number
| Others |
| PEN | Personal Electronic Navigator
| Others |
| PEN | Personal Empowerment Network
| Others |
| PEN | Peruvian Nuevo Sol
| Others |
| PEN | Plywood Edge Nailing
| Others |
| PEN | Poder Ejecutivo Nacional
| Others |
| PEN | Poets Essayists And Novelists
| Others |
| PEN | Poets Essayists Novelists
| Others |
| PEN | Poets, Essayists, Novelists
| Others |
| PEN | Polyethylene Naphthalate
| Others |
| PEN | Poverty Environment Network
| Others |
| PEN | Power Enriched in Nib
| Others |
| PEN | Pre Export Notification
| Others |
| PEN | Primary Endosperm Nucleus
| Others |
| PEN | Private Enterprise Number
| Others |
| PEN | Professional Editors Network
| Others |
| PEN | Prose Essay And Narrative
| Others |
| PEN | Provider Exchange Network
| Others |
| PEN | Public Education Network
| Others |
| PEN | Public Electronic Network
| Others |