A pace runner, or pacer, is a runner who sets out to finish a race in an exact, advertised time so that everyone around them can hit that time too. You spot them by the flag on their back: 4:00, 2:15, 28:00. Stay with the flag and you finish in roughly that time. Simple idea, hard to do well.
What is a pace runner?
A pace runner is an experienced runner who commits to a target finish time and runs it as evenly as they can, acting as a moving clock for the people around them. At big races they are volunteers on an official pace team, carrying a flag that shows their finish time. Ahead of the Big Half in London, organisers told runners to "look out for the runners with brightly coloured flags displaying their target finish times on their backs in your start wave" (London Marathon Events).
The job is part metronome, part cheerleader: updates on the target, reminders to drink, and a calm start when everyone else goes off too fast. Pacers run a time well inside their own ability, so they have spare capacity to talk and react. A seven-hour marathon pacer matters as much as a three-hour one.
How do pacers keep to time?
Pacers aim for steady effort and roughly even splits, then adjust for the course and the weather. The finish time is the target, not identical kilometres.
Ashley Varley, a pacer at Hastings parkrun, wrote on the parkrun UK blog that on a windy morning he told his group they would "head out a few seconds slower, and make up the time on the way back" with the wind behind them. That is good pacing.
GPS cannot always be trusted either. Amber French, a Big Half pacer, warns that around Canary Wharf "GPS can go a bit funny", which is exactly when someone working from mile markers and experience earns their place.
Know the two clocks, too. Gun time runs from the starting signal. Chip time runs from the moment you cross the start line. In a big field the gap can be minutes, which is why where you start matters.
Which UK races have official pacers?
The biggest UK road races generally do, but always check the participant guide for your event, because the times on offer change from year to year. Here is what organisers have published themselves:
- TCS London Marathon. The 2026 pace team had 162 runners, the most in a single year, aged from 25 to 78 (London Marathon Events). The groups go right to the back: 78-year-old Kelvin MacDonald was named to lead the seven-hour group.
- The Big Half, London. Organisers said pacers would cover finish times from 1:30 to 3:50.
- Great North 10k. Great Run's own race guide listed ten pacers covering 40 minutes to 1 hour 20 (Great Run).
Smaller races vary a lot. If a pacer matters to you, check the event page or email the organiser before you enter, not on the start line.
Do parkruns have pacers?
Some do, but do not expect one every Saturday. Pacing is a volunteer role at parkrun, and it varies by event. Hilly Fields parkrun in south-east London, for example, puts pacers out on the first Saturday of each month, with targets from a speedy 17 minutes to a relaxed 40 (GoodGym). Check your event's page or social channels, or ask the run director.
parkrun is also the gentlest place to try pacing yourself. Ashley Varley's advice for anyone tempted: "Choose a time that is around three or four minutes outside the time you are running a 5k in at the moment", then encourage your group. That margin is the whole point. You cannot help anyone if you are on your limit.
Chasing a first sub-30 or sub-25? A pacer Saturday is worth planning around: free, timed, and a person to follow instead of a watch to argue with.
Pacer finish times as pace per km and per mile
Pace flags show finish times, but your watch shows pace. This table converts common pacer targets into what the group should be running. Paces are rounded to the nearest second and assume perfectly even running over the full distance (5 km, 10 km, 21.0975 km for a half and 42.195 km for a marathon).
| Distance | Pacer flag (finish time) | Pace per km | Pace per mile |
|---|---|---|---|
| 5k | 20:00 | 4:00 | 6:26 |
| 5k | 25:00 | 5:00 | 8:03 |
| 5k | 30:00 | 6:00 | 9:39 |
| 10k | 50:00 | 5:00 | 8:03 |
| 10k | 1:00:00 | 6:00 | 9:39 |
| Half marathon | 1:45:00 | 4:59 | 8:01 |
| Half marathon | 2:00:00 | 5:41 | 9:09 |
| Half marathon | 2:30:00 | 7:07 | 11:27 |
| Marathon | 3:30:00 | 4:59 | 8:01 |
| Marathon | 4:00:00 | 5:41 | 9:09 |
| Marathon | 4:30:00 | 6:24 | 10:18 |
| Marathon | 5:00:00 | 7:07 | 11:27 |
Not sure which flag to follow? Put a recent result into our race time predictor for a realistic target, then pick the pacer at, or just slower than, that time.
How do you run with a pacer?
Find them before the gun, start with them, and do not chase.
- Line up beside your pacer. If you cross the start line well ahead of or behind them, your chip time and theirs drift apart by that gap, and the flag stops telling you the truth.
- Do not sprint to catch up. Lost them in the first-mile crush? Close the gap slowly over several kilometres.
- Give them room. Run beside or just behind, and let them through at drinks stations.
- If you drop off, let them go. Settle into your own steady pace. If there is a slower pace group behind you, joining it beats stopping.
- If you feel good late on, go. Ashley described one runner who used him to stay even to halfway, then "steadily pulled away and never looked back" for her quickest run of the year.
How do run clubs use pace groups and pacers?
For most new runners, the first pacer they follow is not at a race. It is whoever leads the 6:30 group on a Tuesday club run. Clubs split runs into pace groups so nobody is out of their depth, and each group leader is, in effect, a pacer. If you organise a club, a few habits make this work:
- Publish a pace, not a vibe. A range like 6:00 to 6:30 per km lets people pick their group before they turn up.
- Pace the slowest person in the group. Not the average.
- No-drop, every time. Nobody finishes alone. Loop back at junctions or put a back marker at the rear.
- Protect the slowest group. Nervous newcomers often start there.
On iPhone, RunClub lets organisers add a pace range to an event and assign club members as pacers, so runners can see the pace before they RSVP. More on mixed-ability sessions in our guide to making your run club inclusive for all abilities, and if you are worried about keeping up, read am I too slow to join a running club?
How do you become a pacer?
Start small and close to home: lead a pace group at your club, volunteer to pace at parkrun, then apply to a race. Each step teaches you to hold a pace that is not your own.
Big races run a formal application, and it is not free. For the TCS London Marathon, London Marathon Events says it welcomes applications from all runners, but most successful applicants have paced or completed the race before and have prior official, in-person marathon pacing experience, with limited places for others. Pacers must be at least 18 on race day, pay an entry fee (£79.99 for UK-based runners), sign a code of conduct, cover a shift at the Running Show and donate reusable kit plus a pair of running shoes.
If leading club runs is the part that appeals, our guide on how to become a run leader in the UK covers the qualification and what the course involves.
Pacer FAQs
Is it cheating to run with a pacer?
No. Official pacers are provided by the race organiser and anyone in the field can follow them, so using one is entirely within the spirit of the event. That is what they are there for. Just give them space and do not block others following the same flag.
Do pacers run to gun time or chip time?
It depends on the event, so check the participant guide or ask at the pace team stand. In practice it matters less than you think: cross the start line alongside your pacer and your chip times will be almost identical.
What should I do if I cannot keep up with my pacer?
Let them go and run your own steady pace rather than surging to hang on. A few seconds per kilometre slower is far better than a walk at mile 20. If a slower pace group comes past, tuck in with them and use them to get home.
Can anyone be a parkrun pacer?
Pacing is a volunteer role, so ask your event team whether they run pacer days and how to sign up. Pick a target comfortably inside your current ability. One experienced parkrun pacer suggests a time three or four minutes slower than you currently run 5k.
Want to practise behind a pacer before race day? Find a club with published pace groups in our run club directory.
