London Marathon 2027 Confirmed as a Two-Day Event: The TCS London Marathon Double Explained

It is the biggest change to the London Marathon since the very first race in 1981. On 19 June 2026, London Marathon Events confirmed what runners had been hearing rumours about for months: the 2027 TCS London Marathon will be a two-day event. They are calling it The Double. Two days, one event, 100,000 people.

This is not a second separate race or a satellite event in another city. It is the same London Marathon, the same iconic route from Greenwich to the finish on The Mall in Westminster, run on two consecutive days for the first time ever. Here is everything that has been confirmed, what it means if you have a ballot place, and how to make sure you are ready if you land one of the 100,000 spots.

What has been confirmed

London Marathon Events (LME), the organisation behind the race, made the announcement official on 19 June 2026. The headline facts are confirmed and not speculation:

• The 2027 TCS London Marathon will run across two days, Saturday 24 and Sunday 25 April 2027.
• A total of 100,000 runners will take part across the two days, roughly double the usual field of around 56,000.
• Both days use the same course, the classic route from Greenwich through Cutty Sark, over Tower Bridge, round Canary Wharf, along the Embankment and finishing on The Mall.
• It is being run as a one-off format for 2027, described by organisers as a one-time celebration rather than a permanent change.
• The decision was driven by a record 1.33 million ballot entries for the 2027 race, the highest number any marathon has ever received.

Hugh Brasher, Chief Executive of London Marathon Events, called it the event's "most ambitious evolution," saying that expanding to 100,000 runners across two days opens doors for "more people, more charities and more communities." Mayor of London Sadiq Khan described the weekend as set to create "the largest fundraising moment in UK sporting history."

The 2027 London Marathon dates

Mark these in your calendar. The full London Marathon weekend for 2027 looks like this:

• Friday 23 April 2027: TCS Mini London Marathon, welcoming more than 20,000 young participants, plus the extended London Marathon Running Show and the new Friday Night Lights 5K.
• Saturday 24 April 2027: Day one of The Double. Mass race plus elite and championship fields.
• Sunday 25 April 2027: Day two of The Double. Mass race plus elite and championship fields.

In a normal year the London Marathon is a single Sunday in late April. The 2027 edition spreads the celebration across a full weekend, turning one race day into a three-day festival of running.

Why London is going to two days

The simple answer is demand. The London Marathon ballot has become the most over-subscribed in the world. For the 2027 race, a record 1.33 million people entered the ballot for roughly 56,000 places. That means well over a million hopeful runners were going to be turned away.

Doubling the field to 100,000 lets almost twice as many people run the race they have been dreaming about, without changing the course, the date window, or the character of the event. It is a one-off response to once-in-a-generation demand, not a permanent doubling of the race.

There is a charity dimension too. More runners means more fundraising. The London Marathon is already the largest single-day fundraising event in the world. Organisers expect the 2027 Double to raise more than £150 million for charity, which would be a record.

How the two days will work

This is the part most runners want to understand. Here is what LME has confirmed about how the two-day format will run.

You will be randomly assigned to one day

Everyone who entered the 2027 ballot goes into a random draw. If you are successful, you will be randomly assigned to either the Saturday or the Sunday race. You do not get to choose your day. Ballot results will be announced in early July 2026.

You cannot run both days in person

The Double is one event run over two days, not two separate races you can double up on. You cannot run the in-person marathon on both Saturday and Sunday. You will be assigned one day and that is your race.

You can add the virtual race on the other day

For runners who want the full experience, you can run your assigned in-person day and complete the virtual TCS London Marathon MyWay on the other day, running your own route wherever you are. That is optional, and only the in-person run gives you the on-course London experience.

How the elite races split across the two days

The elite and championship fields are being divided across the weekend. LME has confirmed the structure, though which group races on which day will be confirmed in the coming months:

• One day will be led by the elite women, elite female para-athletes, championship runners and Good for Age women.
• The other day will be led by the elite men, elite male para-athletes, championship runners and Good for Age men.

This is actually a win for elite-race visibility. Splitting the men's and women's elite fields across two days means each race gets its own dedicated broadcast window and finishing-line moment, rather than competing for attention on a single morning.

What it means for Good for Age, Championship and charity entries

If you have a Good for Age or Championship place, you will be grouped with the elite and faster fields and assigned to the relevant day based on the structure above. If you are running for a charity, your charity place still stands. You will be assigned a day in the same way as ballot runners. The official Charity of the Year for 2027 is the National Autistic Society.

The wider London Marathon weekend

The Double is the centrepiece, but the 2027 weekend is a full festival of running:

• TCS Mini London Marathon (Friday 23 April): Over 20,000 young runners take on shorter distances through central London.
• London Marathon Running Show: The traditional expo at ExCeL London is being extended to cover the bigger weekend, with kit, brands, talks and packet collection.
• Friday Night Lights 5K: A new evening 5K event to kick off the weekend under the lights.

Where the extra fundraising goes

One of the most important parts of the announcement is what happens to the additional income the Double generates. LME has confirmed that all extra income from the two-day event will be distributed by the London Marathon Foundation to fund youth activity projects.

There is a community access commitment too. Every school in London will receive two guaranteed staff entries, and additional entries will be allocated to the London boroughs along the route. It is a deliberate move to make the biggest marathon in the world also one of the most community-rooted.

Is the two-day format permanent?

No. Organisers have been clear that the 2027 Double is a one-off. The plan is for the London Marathon to return to its traditional single-day format from 2028 onwards. If you want to say you ran the one and only two-day London Marathon, 2027 is your single chance.

Does this affect London's World Marathon Major status?

No. The TCS London Marathon remains one of the seven Abbott World Marathon Majors alongside Tokyo, Boston, Berlin, Chicago, New York City and Sydney. The two-day format does not change its Major status or the route. If you are chasing the Six Star (or Seven Star) Medal for completing all the Majors, London 2027 counts exactly as it always has.

What this means if you want to run London 2027

If you entered the ballot, you will find out in early July whether you have a place. If you have a Good for Age, Championship, or charity place, you are in and will be assigned a day. Either way, the smart move is to start preparing now. A spring marathon means a training block that ramps up through the winter, and the runners who succeed are the ones who build a base early rather than panic-training in February.

A first marathon or a target-time London both reward the same thing: a structured plan that fits your real life, builds gradually, and includes the strength work that keeps you healthy through 16 weeks of training. This is exactly where a good training app earns its place.

How Edge gets you to the start line

Edge is the adaptive training app built for runners who want a real plan without hiring a private coach. Here is how it fits London 2027 training, honestly.

When you sign up, a real coach hand-builds your marathon plan within 24 hours, structured around your current fitness, your goal, your weekly schedule, and the equipment you have. From there, Edge AI helps the plan adapt week to week as your fitness changes. It is coach-built and AI-enhanced, not a generic template with your name pasted on top.

For race-day-ready training, Edge pushes every structured session straight to your watch. If you run a Garmin or a Coros, your intervals, tempo runs, and long runs arrive on the watch as structured workouts, so you just hit start and the watch coaches you through each segment. After the run, the completed session imports back into Edge so your plan stays in sync. If you are an Apple Watch runner, Edge has a full native Apple Watch app you can run your sessions from on the wrist.

Strength and mobility are built into every plan, which matters enormously across a long winter marathon block where injuries end more London dreams than fitness ever does. Flexi Swap lets you move sessions around when work and life get in the way, and you can ask Edge AI to adjust your week or speak to a coach whenever you need to. Edge has 17,000+ UK members, a free 7-day trial, and costs £19.99 a month or £119.99 a year. Making fitness feel good for everyone.

Countdown: how long you have to train

Use the planner below to see how many weeks you have until London 2027 and when a typical 16-week or 20-week marathon block should start.

Frequently asked questions

Keep reading

• London Marathon: The Complete Training and Race Guide
• First Marathon 16-Week Training Plan for UK Beginners
• Marathon Day Pacing Strategy: The Complete UK Guide
• Marathon Carb Loading: The Complete UK Guide