O
- O Estado
- O Globo
- O Media
- OACIQ
- Objectif Aquitaine
- Obozrevatel
- Observer Media Group
- Observer Media Ltd. (Uganda)
- Ocean Magazine
- Octomedia
- Odalisque
- OFEM Media Group, S.A. de C.V.
- Off The Grid Publishing Inc
- OffComm News
- Office of the Council of State
- Oh! Life
- Oi Vietnam
- OK-Förlaget
- Okaz Organization for Press & Publications
- Okinawa Times
- Oldie Publications Ltd.
- Ole / Clarin / La Razon
- Om Medya (Turkey)
- Oman Daily/Oman Observer
- Omarest
- Omedia
- Omnimedia
- OMNIMEDIA S.L.
- Omsoc Publishing AB
- ON DIGITAL MEDYA ORGANIZASYON
- One Mega Group
- Online Editora
- Onyx Infinity
- Onze Mondial
- Open Media Atlantic
- Open Media SA
- Opera Actual
- Opera Italia
- Orage AS
- Orage AS - Digital only account
- Orange Fox Media
- Organizacion Editorial Mexicana S.A. de CV
- Oriental Consulting Trading Company
- Oriental Daily News HK
- Orizzonte Italia S.R.L.S
- Orkney Media Group Ltd (Scotland)
- Orlando Sentinel
- Orshanskaya Gazeta
- Oryx Live
- Oslobodjenje doo Sarajevo