NTA
- Demographics of New York City
- NTA Film Network
- Nanoparticle Tracking Analysis
- National Tax Agency
- National Tax Association
- National Telefilm Associates
- National Television Awards
- National Testing Agency
- National Transport Authority (Ireland)
- National Treasury Administration
- National Treatment Agency for Substance Misuse
- Native Title Act 1993
- Natural Science and Technical Academy Isny
- Nepal Telecommunications Authority
- New Transatlantic Agenda
- Newark Teachers Association
- Newton Abbot railway station
- Nigerian Television Authority
- Nitrilotriacetic acid
- Northern Territory Administration
- Nuclei Territoriali Antimperialisti