It comprised the FIA GT Championship for Drivers, the N-GT Cup for Drivers, the FIA GT Championship for Teams and the N-GT Cup for Teams.
[1] The four titles were contested over a ten event series open to Grand Touring cars broken into two classes, GT and N-GT,[1] based on power and manufacturer involvement.
The 2003 FIA GT Championship for Drivers was won by Matteo Bobbi & Thomas Biagi driving a Ferrari 550 Maranello for BMS Scuderia Italia.
The 2003 N-GT Cup for Drivers was won by Marc Lieb & Stéphane Ortelli driving a Porsche 911 GT3-RS for Freisinger Motorsport.
Points were awarded to the top 8 finishers in the order of 10–8–6–5–4–3–2–1 except at the Spa 24 Hours, where an additional allocation of half points were awarded to the leaders at both the six-hour mark and the twelve-hour mark.