The 2013 Avon Tyres British GT season was the 21st season of the British GT Championship. The season began on 30 March at Oulton Park and finished on 6 October at Donington Park, after ten rounds held over seven meetings. Beechdean Motorsport team principal Andrew Howard won the GT3 category in an Aston Martin V12 Vantage GT3, Optimum Motorsport's and Rick Parfitt Jr. won the GT4 championship, driving a Ginetta G50 while and took the GTC title in a Ferrari 458 Challenge, driving for Horsepower Racing.