Unique opportunity to stage races on Saturday and Sunday in the British capital next year could generate £400 million worth of economic and social benefit.

Behind the scenes, the London Marathon staff are simply calling it "the double". The exciting plans involve staging two marathons next year on Saturday and Sunday – one mainly for women, the other largely for men – with potentially huge benefits when it comes to raising charity money, an economic boost, plus the sizeable social uplift that the event has been synonymous with since 1981.

Whether it is a success or not, though, London Marathon event director Hugh Brasher insists "the double ... will be one and done."

Brasher says: “We believe that more than £130m would be raised for good causes and £400m of economic and social benefit would come to this country – that’s from research done at Sheffield Hallam [University]. We think it would be absolutely amazing and it is something that we’ve been working on for a long time."

The idea for the London Marathon to dominate two entire days in 12 months' time is hugely ambitious, but Brasher says he is inspired by a Robert Browning quote that his father, London Marathon founder Chris Brasher, was fond of: "A man's reach should exceed his grasp, or what's a heaven for?"

He adds: “The idea has also so far been overwhelmingly positively received."

Firstly, however, Brasher needs to get a large number of stakeholders on board with the idea ranging from the police and transport networks to the Mayor and London Boroughs. Even if the idea comes off – and it must surely be close to being agreed given that Brasher is now talking about it so openly – he is cautious about making it an annual affair.

"You have to bear in mind that the London Marathon has been going for 45 years and it’s got to a position of love, not only the sporting calendar but the calendar of London. You can lose that love very quickly and we have to be mindful of that. And that is why it is very much a one and done.”

Brasher says his team also have many other goals that they want to focus on, such as expanding the Mini London Marathon to around 50,000 participants by 2030.

So, while it looks like being a one-off, Brasher emphasises the need to do it at least once – and why now is the perfect time. "There is a need in this country to do it," he says.

READ MORE: London Marathon preview

Brasher says one of the original founding pillars of the London Marathon was to show some joy and happiness to a somewhat troubled world. "And those words resonate more now in 2026 than they did in 1981," Brasher says.

In an age dominated by social media and the advent of artificial intelligence, Brasher also feels people are likely to continue seeking real-life moments and experiences, such as running London, more and more.