The London Marathon is set for its biggest transformation yet, with organisers confirming that the iconic race will become a two-day event in 2027, a historic, one-off expansion designed to accommodate record demand and boost fundraising efforts.
First held in 1981 with just 7,747 runners, the London Marathon has grown into one of the world’s most celebrated sporting events.
London Marathon will be held across two days in a special one-off edition of the event in 2027
Now, for the first time, it will take place across two days – Saturday 24 April and Sunday 25 April 2027, allowing a record 100,000 participants to take part.
The decision comes after unprecedented interest, with more than 1.33 million people entering the ballot for the 2027 race, surpassing the previous record set for 2026.
By doubling the number of runners, organisers aim to significantly increase participation while maintaining the event’s global appeal.
Hugh Brasher, chief executive of London Marathon Events, described the move as a “once-in-a-generation” moment.
London Marathon 2027 could potentially raise over £150 million for charitable causes
He said the expanded format will open doors for more runners, charities, and communities, while potentially raising over £150 million for charitable causes.
The wider economic impact is also expected to be substantial, with estimates suggesting a £400 million boost to the UK economy.
“This is our most ambitious evolution to date,” Brasher said. “By expanding to 100,000 runners across two days, we’re creating an even bigger celebration of activity and community across London.”
Under the proposed format, elite and mass participation races will be split across the two days, with women’s races expected to take place on one day and men’s on the other. Full details are yet to be confirmed, but all runners will follow the traditional marathon route from Greenwich to Westminster.
Participants who entered the ballot will automatically be considered for both race days, with results expected in early July.
Organisers have confirmed that the Sunday race, the marathon’s traditional slot will be allocated first, followed by a second ballot draw for Saturday places.
London Mayor Sadiq Khan welcomed the announcement, calling it a testament to the city’s status as a global sporting capital.
“For one year only in 2027, the world-famous London Marathon will expand into a two-day event, an exciting moment for our city and for sport,” he said.
2026 London Marathon already set new benchmarks, with a record 59,830 finishers and more than £90 million raised
The 2026 London Marathon already set new benchmarks, with a record 59,830 finishers and more than £90 million raised for charity, reinforcing its status as the world’s largest annual one-day fundraising event.
Organisers now hope the 2027 edition will go even further, with additional funds distributed through the London Marathon Foundation to support projects encouraging physical activity among young people.
Despite its scale, Brasher has emphasised that the two-day format will be a one-off, introduced in response to what he called an “astonishing” level of demand. Plans for expansion had been in development for nearly a decade but only recently received the necessary approvals.
Alongside the main event, the Mini London Marathon will return on the Friday, featuring over 20,000 young participants and further cementing the marathon weekend as a city-wide celebration of sport and community.
