Brands
- Newell Harding
- Newmans
- Newport
- Nissens
- No Brand
- Nolan Miller
- NOMOS
- Nomura
- NP
- NRA
- Nurit & Shoshana Bar-On
- O Reed
- O'Torzal
- OFF-White
- Official Standard Ball
- Oldsmobile
- Oliva
- Olympia Le Tan
- OMD
- Omega
- ONEIDA
- Orient
- ORIENT STAR
- Oris
- Oris Aquis
- Oris Maldives
- Oris Titan
- Orodeus
- Oroton
- OWC
- Oyster Watch Co
- P Q