The UK hosts four huge horse racing festivals each year and, throughout history, they have consistently seen the leading trainers enter horses into their races.

The quartet of multiple-day meetings are evenly split between the jumps and flat format. Jump racing takes the spotlight each year, with the Cheltenham Festival and the Grand National taking place across March and April. Royal Epsom and Royal Ascot then provide flat racing’s strongest offerings in May and June.

This year, the four events have now passed, with several iconic trainers solidifying their reputations within the sport by securing major victories. Here we will look at the top trainers at each major festival, exploring what are ultimately the best trainers in these races’ history.

Willie P. Mullins is Cheltenham’s Greatest Ever

Willie P. Mullins is undoubtedly the most successful trainer in the history of the Cheltenham Festival, with 103 wins after leading nine race champions out in 2024.

Perhaps most significantly, he has trained two multiple-time Gold Cup winners in Al Boum Photo and Galopin Des Champs – the latter of which could secure Mullins’ fifth overall success in the festival’s standout event next year.

The 2023 and 2024 double champion is the favourite to win again in 2025 across many major bookmakers, who have betting offers on UK major sporting events for the remainder of the year and beyond.

Paddy Power, for example, offers Galopin Des Champs as a 7/2 favourite to become only the second-ever three-time champion next March. They’re offering £50 in free bets for an initial £10 stake on any sporting event taking place in the future.

Ultimately, Mullins’ Gold Cup winners are his greatest Cheltenham projects – and his latest double-winner could go on to secure a legacy as the festival’s greatest-ever horse – although every single race winner has contributed to his position as Cheltenham’s most successful trainer.

Fred Rimell Outshines His Fellow National Winning Trainers

Fred Rimell, Ginger McCain, and George Dockeray all won the Grand National as trainers four times during their careers.

However, it is Rimell’s feat that represents the greatest level of success when looking back through history. He won with four different horses, unlike McCain, and captured his victories in a more competitive period. Dockeray, in comparison, won between 1839 and 1852 when the Grand National was still a regional meeting.

Rimell’s first triumph came via E.S.B in 1956,.Nicolaus Silver followed in 1961 and Gay Trip won in 1970 before Rag Trade rounded out his victories six years later.

With McCain having won his three Nationals in the 1970s and adding a fourth in 2004, some would argue his achievements were greater as they came across different generations of the sport. However, the fact that Rimell led different horses to victory on each of his triumphant Aintree visits cannot be overlooked.

Aiden O’Brien’s Derby Record Makes Him Epsom’s Standout

The Epsom Festival is home to many significant races, although the Epsom Derby holds the greatest significance by far. The record winner in terms of Derby trainers is Aiden O’Brien, who in the 21st century has created a legacy as one of Epsom’s most legendary names.

He led 10 different horses to success at the flat racing’s landmark event, which began with Galileo in 2001. The most recent success came through City Of Troy in this year’s Derby.

O’Brien is arguably one of flat racing’s all-time greats, considering his success across a variety of venues. His long-term success in the Derby represents his greatest achievement though, and makes him Epsom’s most successful trainer ever.

O’Brien Is Also Royal Ascot’s Most Successful Trainer

O’Brien is not only the most successful trainer in the history of the opening flat racing multiple-day event each year, but in the closing festival of the year too.

The Irishman has enjoyed a remarkable 92 victories throughout the participation of his horses at Royal Ascot. He passed Sir Michael Stoute’s tally of 82 race wins in 2023 as he finished the year on 85, and this year a further seven wins have seen him edge towards an Ascot century.

His position as the most successful trainer in both of the UK’s biggest flat racing festivals is evidence that he is one of the greatest developers of talent in the format overall – maybe the greatest.

Ultimately, two different individuals stand out as the all-time greatest trainers in the jump racing festivals. However, when it comes to flat racing, one man has dominated at both Epsom and Ascot and has a strong claim to being the most successful trainer in the history of UK festivals overall.