| Acronym | Definition |
|---|
| NPO | Non-Profit Organization |
| NPO | Newport (Amtrak station code; Newport, OR) |
| NPO | Nuclear Plant Operator |
| NPO | National Printing Office (Philippines) |
| NPO | New Pacific Order (Cybernation alliance) |
| NPO | North Pacific Oscillation (meteorology) |
| NPO | New Polar Order (Cybernations Alliance) |
| NPO | No Particular Order (band) |
| NPO | National Program Office(r) |
| NPO | Negative and Positive to Zero |
| NPO | Nagoya Philharmonic Orchestra (Japan) |
| NPO | Nederlandse Publieke Omroep (Dutch public broadcasting system) |
| NPO | Non-Product Output |
| NPO | Nurses Professional Organization |
| NPO | National Productivity Organization |
| NPO | Net Power Output (electric power) |
| NPO | Northern Physicians Organization (Traverse City, MI) |
| NPO | Nil Per Os (Latin: Nothing by Mouth) |
| NPO | Naval Port Officer (US Navy) |
| NPO | Non Productive Overtime |
| NPO | Network Performance Objectives (ITU-T) |
| NPO | Non Per Os (Latin: Nothing by Mouth) |
| NPO | National Public Health Officer |
| NPO | National Public Observatory (Radium Springs, NM) |
| NPO | Nulla Per Os (Latin: Nothing By Mouth, also Non/Nil Per Os) |
| NPO | Nucleus Preopticus |
| NPO | Navy Purchasing Office |
| NPO | New Personnel Orientation |
| NPO | Naval Petroleum and Oil Shale Reserves |
| NPO | Naval Project Office |
| NPO | National Platform Operations (Sprint) |
| NPO | Navy Program Objective |
| NPO | NWTS Program Office (US DOE) |