| Abbreviation | Definition |
|---|---|
| NATF | National Air Transportation Foundation |
| NATI | North American Transportation Institute |
| NATL | National Agricultural Transportation League |
| NATP | Nebraska Association of Transportation Providers |
| NATS | National Air Traffic Services |
| NATS | National Automated Travel System |
| NATS | North Arkansas Transportation Se |
| NATS | North Arkansas Transportation Service |
| NATSA | North American Transportation Services Association |
| NAVMTO | NAVy Material Transportation Office |
| NAVSTAR | Navigation Satellite Timing and Ranging System |
| NAWPF | National Aviation Weather Processing Facility |
| NAX | North American Express Transportation |
| NB | NorthBound |
| NBB | National Biodiesel Board |
| NBBIT | National Biodiesel Board - Information Technology Division |
| NBI | National Bridge Inventory |
| NBIS | National Bridge Inspection Standards |
| NBMB | National Bus Military Bureau |
| NBS | No Bicycle Sign |