| Abbreviation | Definition |
|---|---|
| NSSC | National Safety and Security Council |
| NSSC | National Senior Service Corps |
| NSSFC | National Sample Survey of Fertility and Contraception |
| NSSFC | National Social Security Fund Council |
| NSSHLA | National Student Speech Hearing and Language Association |
| NSTA | National Space & Technology Association |
| NSTC | North Shore Technology Council |
| NSTF | Nova Scotia Trails Federation |
| NSTL | North and South Trust Limited |
| NSWF | Naval Special Warfare Foundation |
| NSWMA | National Solid Waste Management Association |
| NTAF | National Taxpayers Against Fraud |
| NTAF | National Transplant Assistance Fund |
| NTAG | Nepali Technical Assistance Group |
| NTC | National Trails Coalition (Canada) |
| NTD | National Theatre of the Deaf |
| NTDAAM | National Trust for the Development of African- American Men |
| NTEE | National Taxonomy Of Exempt Entities |
| NTEE-CC | National Taxonomy of Exempt Entities- Core Codes |
| NTEN | Nonprofit Technology Enterprise Network |