London Marathon just confirmed its biggest-ever change for 2027 and 100,000 runners will benefit

Runners cross Tower Bridge during the London Marathon April 27, 2025 in London, England. — (Image credit: Leon Neal/Getty Images)

After months of speculation, the TCS London Marathon has officially confirmed that its 2027 event will take place across two days for the first time in the race's history.

Dubbed the London Marathon Double, the event will be held on Saturday 24 April and Sunday 25 April 2027, with organisers expecting a record-breaking 100,000 runners to cross the finish line over the weekend.

The move comes after a world-record-breaking race in 2026, and demand for places reached unprecedented levels.

A one-off event designed to let more people run

London Marathon Events describes the Double as a "once-in-a-generation" reimagining of the event rather than a permanent change.

The current plan is for the race to return to its traditional one-day format in 2028.

Both days will feature the full 26.2-mile course, with runners assigned either Saturday or Sunday. Participants will only be able to run once during the weekend.

Elite women, female wheelchair athletes and women's championship runners will compete on one day, while the men's elite and championship races will take place on the other.

The expansion could have a huge impact beyond participation numbers.

Two London Marathon finisher medals from 2022 and 2023

Organisers believe the event could raise more than £150 million for charity and generate around £400 million in economic and social benefits for the UK.

For runners, though, the biggest takeaway is simply more places.

While securing a London Marathon spot is still likely to be highly competitive, the Double means that tens of thousands more people will have the chance to experience one of the world's most iconic races.

And if the 2027 experiment proves successful, don't be surprised if calls for a permanent two-day London Marathon grow even louder.

[via London Marathon Official website]

Matt Kollat is a journalist and content creator for T3.com and T3 Magazine, where he works as Active Editor. His areas of expertise include wearables, drones, action cameras, fitness equipment, nutrition and outdoor gear. He joined T3 in 2019.

His work has also appeared on TechRadar and Fit&Well, and he has collaborated with creators such as Garage Gym Reviews. Matt has served as a judge for multiple industry awards, including the ESSNAwards. When he isn’t running, cycling or testing new kit, he’s usually roaming the countryside with a camera or experimenting with new audio and video gear.