Pacing tips and advice for London Marathon 2023

London Marathon 2023 is on Sunday 23 April 2023 and if you’re taking part you will probably have some idea of a finishing time you’d like to achieve and therefore a pace you’re going to aim to run at.

It’s not going to be that easy though and this article will detail the multiple factors you need to take into account that can affect your target time.

Even if you’ve trained perfectly there are always on the day elements that can affect your pacing such as the weather, course elevation, and in the case of the London Marathon the sheer number of people taking part.

Pace Calculator

If you don’t know your target pace but have a rough finishing time, simply use the calculator below, select ‘Marathon’, enter the target time, and click ‘calculate’ to get that average pace time. You can also view our pace charts too.

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Remember, you’re allowed to have an idea of the time you’d like to finish but your first priority should be to finish the race, and then second priority is your time.

By making finishing your number one priority, you are lowering the pressure on yourself, and appreciating that completing a marathon is an amazing achievement that many people will never do. Read our ‘10 tips to help you complete a marathon‘ article for more advice.

Average Finishing Times

Below are the average finishing times (rounded down to the nearest minute) for London Marathons between 2017 and 2022, but remember that there are just an average of all the runners’ finish times, and never something you should judge yourself against. If you get World Record holder Eliud Kipchoge and his mates running the marathon then the average time is going to drop!

YearAverage Finish Time
20174 hours 30 minutes
20184 hours 50 minutes
20194 hours 30 minutes
2020Only elites ran due to Covid
20214 hours 28 minutes
20224 hours 35 minutes

Average times collated from

A flat(ish) but busy course

The London Marathon takes place on closed roads and pavements throughout the city and with a total elevation of less than 150m over the 26.2 miles it is considered a ‘fast’ and fairly flat course. It is quite a twisting route though with many of these turns creating bottlenecks, which may not affect faster runners, but will definitely cause issues for the majority of runners taking part.

London Marathon 2023 Map
© OpenStreetMap contributors, CC BY-SA 2.0, via Wikimedia Commons

With over 40,000 runners taking part it can be hard to initially keep to the pace you initially had in your head. Even though groups set off in waves based on predicted finish times, it still leads to a congested startline.

London Marathon Waves
Image courtesy of Tom Benjamin

You will be running very close to other people so you want to be careful to avoid a trip or a fall. Understand you may be a little slower getting out the corales, but it’s really not worth trying to overtake people, or weave around runners, as you will needlessly burn energy.

Keep relaxed for the first half knowing it will start spacing out and you can efficiently keep to your target pace.

Be aware of GPS blackspots

There are a lot of tall buildings in London and GPS watches can struggle on the section through Canary Wharf meaning you may get some dodgy splits and times. Use your GPS as a guide, but remember you’re running to the course markers, not what your Garmin says.

You will run longer than a marathon

During the marathon you will see a blue line on the course that dictates the most direct line around the marathon and is what the official measurement of 26.2 miles counts.

Your chances of sticking to this line for the whole race is virtually zero, so you’ll hit marathon distance before you actually cross the finish line.

The Weather

London Marathon has switched back to it’s more traditional April date for 2023 after the 2020, 2021, and 2022 races were held in October, and this could mean a higher chance of warm weather affecting your run.

YearPeak Temperature
2015 (26 April)12°C (54°F)
2016 (24 April)9.6°C (49°F)
2017 (23 April)17°C (62°F)
2018 (22 April)24.1°C (75.4°F)
2019 (28 April)14°C (57°F)
2020 (4 October)11°C (52°F)
2021 (3 October)17°C (63°F)
2022 (2 October)19°C (66°F)
2023 (23 April)???

Temperature data collected from

In fact we only have to go to the April 2018 for the hottest London Marathon where temperatures reached 24.1ºC. This was recorded at St. James’s Park so we’ve sourced the historic temperatures for other recent years in that area to see how they compare.

Looking at the recent October events you can see that there is still a chance for a hot day but with with the bulk of your training occuring during the winter months this heat can come as a bit of a shock so be prepared. Bring a variety of clothing, sweat-resistant sunscreen, a running hat, but also be prepared to adjust your pace and finish times aims.

On hot days you will also find that the first few water stations have a high demand so it’s worth having your own disposable bottle to start with so you can concentrate on running. If you have agreed to meet supporters along the route then it’d be handy if they had a bottle (with a sports lid) with them that you can take if needed.

If it’s a cooler day, then also be prepared to bring an old hoody or sweatshirt with you on the day which you can discard (and be collected by charities) before you start the race.

Finally, be prepared for some odd headwinds caused it built up areas, where the high-rise office blocks, can channel strong winds. This can not only affect your pace but also sap your energy.

Pacing tips and advice for London Marathon 2023 1
Photo by Dan Huddleston

We all gotta pee

Make sure you get in line for the portaloos as soon as you get to the race area. You may feel the need for it, but queues can be long and you’ll probably be grateful by the time you get to the front!

There is nothing worse that needing the toilet just before the race so this can buy you some time. The first few toilets along the route will be busy, but they are spaced out every two miles so you will be able to get going before needing another wee.

Follow the pacers

If you’re worried about keeping pace, or really want to hit a specific time then you can follow one of the official pacers who complete the course at a managed pace and finish within a certain, predesignated time.

At the 2022 London Marathon there were pacers running at 15 minute intervals from 3 hours through to 7 hours 30 minute. These are present throughout the different waves and not only do they give you someone to follow and keep up with, they are also a friendly bunch who will offer words of encouragement to those who stick with them.

As these pacers know the route very well, they may vary the pace at different times, rather than a constant pace, as they anticipate variations to the route, so just be aware that they may pick up the pace or slow it down on certain stretches.


There are dozens of other factors that can affect your pace and finish time for London Marathon, such as how much sleep you’ve had, your hydration throughout the week, how you’ve been training, and even if you’ve had a cold the week before.

A lot of those can be out of your control though, and you have to accept that, but hopefully this article will have given you a better understanding of the race day factors at the marathon that are in your control.

Ultimately remember your main aim is to finish the marathon, but we all want to get the best time we can right? So go out there and enjoy London Marathon 2023!

Adem Djemil
I only started running at the age of 37, completing the Couch to 5k course, and since then I've been hooked, running 4 times a week and even completing several marathons and an ultra!

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