Teams: O

O2

• O2 Racing Technology USA

Oa

• Oak Racing France

Ob

• Obaika Racing USA
• Obermeier Racing Germany
• O'Brien Motorsports USA

Oc

• Ocean Racing Technology Portugal
• O'Connell Racing USA
• octane126 Switzerland
• Octanos Competición Argentina

Od

• OD Racing Malaysia

Og

• O'Gara Motorsport USA

Ok

• Okayama / Carlin Japan
• Okayama Team Japan

Ol

• Olimp Racing Poland
• Oliver Mayer Motorsport Germany
• Olivier Baron France
• Olsson Engineering USA

Om

• Ombra Racing Italy
• Omegaland Great Britain
• Omicron Racing Spain

On

• One Formula Racing USA
• One Motorsports USA
• One Racing Italy
• One11 Competition USA
• Onyx Racing Great Britain

Op

• Optimum Motorsport Great Britain
• Optirace Sport France

Or

• Orange Racing Great Britain
• Orangino Racing Team Mexico
• Orbit Motorsport Italy
• Orbit Racing USA
• Orea Ross Racing Mexico
• Oregon Team Italy
• Orhes Team Compétition France
• Origine Motorsport China
• Orion Canada
• Orion Motorsports USA
• ORMS Racing Germany
• Oryx Dyson Racing USA
• Oryx Racing USA

Os

• Osella Italy

Ov

• Over Drive France

Ow

• Owen Osborne Australia
• OWL Competições Brazil