NCOI
| Acronym | Definition |
|---|---|
| NCOI | National Committee on Inquiry (National Association of Social Workers) |
| NCOI | National Competition in Organ Improvisation (American Guild of Organists) |
| NCOI | Nederlands Commercieel Opleidings Instituut (Dutch: Dutch Commercial Training Institute) |
| NCOI | North County Orthopedics, Inc. (Missouri) |
| NCOI | National Congress on Integrity |