The 2003 Proximus 24 Spa was the 56th running of the Spa 24 Hours and the sixth round the 2003 FIA GT Championship season. This event combined the FIA GT's two classes (GT and N-GT) with cars from national series and one-make series, designated G2 and G3. It took place at the Circuit de Spa-Francorchamps, Belgium, on July 25 and 26 2003.
This race marked the only time in the history of the FIA GT Championship that the slower of the two classes (N-GT in this case) managed to win a race overall.
For the FIA GT Championship, the top eight cars in the GT and N-GT classes are awarded half points for their positions after six hours and twelve hours into the race. Points to the top eight were awarded in the order of 4.0 – 3.0 – 2.5 – 2.0 – 1.5 – 1.0 – 0.5.
Class winners in bold. Cars failing to complete 70% of winner's distance marked as Not Classified (NC).