The British Champions Series was a series of 35 top British flat races, which culminated in a day-long festival of championship races, known as British Champions Day. It was inaugurated in the 2011 season to draw together some of Britain's key flat races into a meaningful championship, with the hope of generating coverage and stimulating interest among the more casual sports fan. It was believed to have achieved its aims based on an increase of 7% attendance at the race days that were part of the 2011 series, as opposed to a 3.9% increase in attendances across the season's race programme as a whole.
The championships were sponsored by the Qatari investment group QIPCO since its inception in 2011. In June 2015 QIPCO renewed their sponsorship until at least 2024 in a deal worth more than ã50m, the biggest sponsorship deal ever for British horse racing.
The series was split into five divisions - Sprint, Mile, Middle Distance, Long Distance and Fillies & Mares. This series included all Group One races in Great Britain, except those limited to two year old horses.
The series was discontinued in 2025.