| Abbreviation | Definition |
|---|---|
| PNO | Public Network Operator |
| PNOC | Phil National Oil Company |
| PNOC | Philippine National Oil Company |
| PNP | Paul Nicholls Productions |
| PNP | Princeton Nassau Pediatrics |
| PNPC | Prime National Publishing Company |
| PNSC | Pakistan National Shipping Corporation |
| PNTC | Portland North Truck Center |
| PNTL | Pacific Nuclear Transport Ltd |
| PNTN | Professional National Title Network |
| PNX | Pacific North Express |
| PO | Pamatnik Odboje |
| PO | Payoneer |
| PO | PortugalOriflame |
| PO | Pump Operator |
| POA | Peachtree Office Accounting |
| POA | Pillar of Autumn |
| POA | Ponies Of America |
| POA | Prosthetic Orthotic Associates |
| POAC | Professional Outplacement Assistance Center |