How to Set Up Registration for an Ultramarathon: Vetting, Waitlists and Crew

Amit K · November 12, 2026

Registration for ultramarathons: a race director’s guide from endurace.pro

It is 3 a.m. on a mountain, the nearest road is hours away, and a runner has missed a cut-off she says nobody explained. Most of that story is decided months earlier, at registration.

An ultramarathon is any race longer than a marathon, from a 50 km trail race to a 100-mile mountain run, and some are timed events that last 12 or 24 hours. The courses are long and remote, and a lot can go wrong. Registration is where you decide who gets in, make sure they understand the demands, and collect what crew and medical teams rely on. This guide shows how to set that up.

Distances, cut-offs and capacity

Most ultras offer one or more distances, for example 50 km, 100 km and 100 miles, each with its own start time and cut-off.

Spell out the cut-offs for the finish and for each checkpoint. A runner who understands them in advance is less likely to be pulled from the course in the middle of the night.

Capacity is set by your permits, aid stations and marshals, so decide it for each distance before you open registration.

Vet your entrants

Many ultras need some evidence that a runner can handle the distance. Ask for qualifying information as part of entry: the longest race the runner has finished, their best marathon time as a time (for example 3:45:00), and any previous finish at your event.

You can then review the list before race day and decide who needs a conversation.

Where you want places for invited runners, such as elites, past winners or sponsors, use a hidden ticket that opens only with a private code or link.

Ask about crew and pacers

Many ultras allow crew and pacers, with rules about where they may help and when they may join. Ask each runner for the number of crew members and for the name and phone number of a crew contact.

That helps you size your crew parking and aid areas, and gives your team a number to call if a runner leaves the course.

Safety, medical and waivers

Every runner needs an emergency contact and, ideally, a blood group. If you ask about medical conditions, keep the question optional, explain why you are asking and ask only what you will use.

Keep a clear, versioned waiver, with the exact wording, the name typed and the time of acceptance attached to each entry. Your medical team should be able to open one list of emergency contacts and medical information on race morning.

Waitlists and drop-outs

Ultras are demanding, and some entrants drop out in the months before the race because of injury or other commitments. A waitlist that offers each freed place to the person who has waited longest, with a fixed window to accept, keeps your field full and fair.

Because the field is small, every place matters.

Refund policy

Publish a tiered refund policy before entries open, with dates. Long races attract entrants who travel, so state clearly what happens if you cancel for safety or weather, and how you will tell people.

In practice: a made-up example

Example only, not a real event. Imagine a mountain race with a 50 km and a 100 km. On the 100 km you ask a time question for best marathon time, a text question for the longest race finished, a number question for crew size and a tick-box to confirm the runner has read the cut-offs. A hidden ticket, unlocked by a private link, holds a few places for past winners.

When the 100 km sells out, a waitlist button appears. If someone withdraws, the place is offered to the longest waiter, who has 24 hours to take it. Before race day you export the registration list, with blood group and emergency contact, for your medical team.

Common mistakes

First come, first served with no vetting. It fills the field with people who are not ready.
No crew information. Your team has no one to call if a runner leaves the course.
Cut-offs mentioned once. Put them in the form and the confirmation email.
No waitlist. Every drop-out is a place lost.

Set it up on endurace.pro

Several distances per event, each with its own price, capacity, and distance in km or miles.
Your own questions per distance: a time question for best marathon time, a text question for races finished, a number question for crew size, and a tick-box for cut-offs.
Hidden tickets for invited runners, unlocked by a code or link.
A waitlist that is on by default, with a 24-hour hold on each offered place.
Waivers kept per registration, plus date of birth, blood group and emergency contact in a CSV you can export for your medical team.
A tiered cancellation policy on the event page, and a one-step full refund for everyone if you cancel the event.

Quick answers

How do I reserve places for invited runners? Use a hidden ticket, unlocked by a private code or link.

What happens when someone drops out? The waitlist, on by default, offers the place to the person who has waited longest, with a 24-hour hold.

Can I ask for a best marathon time? Yes, as a time question per distance. It rejects anything that is not a time.

How does my medical team get the details? Export the registration list as a CSV, which includes blood group and emergency contact.

Summary graphic: seven things to settle before ultramarathon entries open: distances and cut-offs, capacity and permits, qualifying information, crew and pacer details, emergency and medical info, waitlist and invites, and refund policy.

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