RunSignup puts out a comprehensive annual RaceTrends report looking at the state of the endurance industry. However, one of the largest gaps in that report is the state of Ultramarathons. While data exists, our bulk reporting cannot differentiate between long-term virtual challenges and true ultramarathons, and some long distance bike rides get misclassified.
This is our first in-depth look at 2025 ultramarathon statistics using data we know is from true ultramarathons. It’s likely still imperfect and missing some events, but it is a decent starting point to understand the landscape of ultramarathons.
This report looks at 728 ultramarathon events across 418 races, representing 50,220 participants. In 2025, Ultrarunning Magazine reported that there were 1995 races with at least one ultramarathon distance, with 3270 ultramarathon events* and approximately 150,000 finishers. That suggests that this RunSignup data represents 1/4 to 1/3 of all US ultramarathon data.
* Ultrarunning Magazine defines races and events opposite of RunSignup. For consistency in our reporting, we are using the RunSignup definitions, in which “Event” means the single-distance event and “”Race” represent the full race weekend.
What is an Ultramarathon?
Ultramarathon is a broad term meaning any event longer than a marathon (26.2 miles). Typically, they range from 50K (31.1 miles) to 100 miles, although races of 200+ miles also exist. Additionally, for the purposes of this report, we included two other categories that are not always ultramarathons:
- Timed races where the winner is the one who runs the furthest within a set time range. We included timed races of 6+ hours.
- Backyard races (or “Last Man Standing” races) have a specific loop/distance that is run each hour (typically 4.167 miles). The winner is the runner who can run the most hours while completing the distance within that time.
In both cases, it is possible that not every registered runner completes an ultramarathon, but we opted to include them because some runners will complete an ultramarathon and they typically appeal to similar types of runners.
50Ks Dominate the Ultramarathon Market
Unsurprisingly, 50K’s – the most accessible ultramarathon distance – make up the greatest share of both available ultramarathons, and ultramarathon participants. Fifty milers follow with 12% of all events and 17% of participants. Meanwhile, timed races make up nearly a quarter (24%) of all events, but host just 12% of all participants.
Ultra Events
Ultra Participants
Average Ultramarathon Field Sizes Remain Small (for good reason)
While some ultramarathon races do host thousands of participants, the organizational logistics and training challenges make smaller events the default. 100 milers are the largest (on average), with just over 100 participants while 6-Hour races average just 22 participants.
These numbers include only the average in a single event, while many races offer multiple event distances. In many cases, a single race hosts multiple events (like a 6 Hour, 12 Hour, and 24 Hour) utilizing the same course. This allows races to appeal to a wider audience while maintaining low overhead.
Of note: it’s not just ultramarathons that are small. While non-ultra races average slightly more participants (125), most events are small.
Runners Per Event
When and Where are Ultramarathons?
Like races of all distances, ultras are most common in the fall, with 13.2% of races in October. However, there are some differences compared to all races.
First, ultramarathons are more evenly distributed across the year than all races. Each month hosts between 6-13% of ultramarathons. Meanwhile, the month with the fewest overall races (January) hosts just 3% of races, while the most popular month (September) has 14% of all races. Perhaps the runner who is willing to run for 6+ hours is also more likely to be willing to deal with adverse weather conditions.
Secondly, the summer is a slower season for ultramarathons than for all races. This is likely due to the increased risks of super-long-distance running in high temperatures.
Races by Month
Where Are Ultramarathons?
The short answer: ultramarathons are pretty much everywhere. Forty-six states hosted at least one ultramarathon on RunSignup in 2025. The most popular states included Texas, Colorado, California, and Utah.
Of note: because many ultramarathon organizers put on multiple races each year, the locations can be impacted by a few high-productivity RunSignup customers in specific states.
Top 10 States
The Demographics of Ultramarathons: Majority Male and 30-49
Understanding demographics helps race directors target their promotions and create experiences that appeal to their audience.
Ultramarathons and Gender
Men are more likely to sign up for ultramarathons, with men making up 65% or 50K runners and 76% of 100 milers. Timed events narrow the gap a bit, with women making up 44% of 6-Hour runners and 46% of 24-Hour runners.
Note: N/A/Other gender indicates either the race did not collect gender, or used custom options beyond male, female, and non-binary.
Participants by Gender
Ultramarathons and Age
Unsurprisingly, the vast majority of ultramarathoners are adults (less than 1% are under 18). Runners in their 30’s and 40’s make up more than half of all participants. While 30-somethings make up the largest share of “shorter” ultra distances, 100 milers and timed events are most popular with those in their 40’s.
While there is a participation drop-off as runners age, some ultramarathoners stick around, with 6% of participants over 60.
Note: N/A indicates the race did not collect age.
Participants by Age
| Category | <18 | 18-29 | 30-39 | 40-49 | 50-59 | 60-69 | 70-79 | 80+ | N/A |
|---|---|---|---|---|---|---|---|---|---|
| 50K | 0.5% | 18.2% | 29.6% | 25.2% | 13.8% | 4.4% | 0.7% | 0.0% | 7.6% |
| 50M | 0.2% | 19.7% | 29.8% | 26.0% | 13.0% | 3.8% | 0.7% | 0.1% | 6.9% |
| 100K | 0.4% | 13.2% | 33.0% | 27.3% | 13.4% | 4.4% | 0.4% | 0.0% | 7.7% |
| 100M | 0.1% | 12.3% | 27.1% | 29.1% | 14.9% | 4.4% | 0.9% | 0.0% | 11.2% |
| 6 Hour | 2.1% | 13.0% | 27.3% | 27.9% | 16.0% | 7.1% | 2.2% | 0.3% | 4.2% |
| 12 Hour | 4.3% | 12.1% | 23.9% | 27.4% | 17.1% | 9.2% | 2.6% | 0.3% | 3.2% |
| 24 Hour | 4.2% | 9.2% | 17.4% | 24.8% | 22.6% | 13.0% | 5.1% | 0.7% | 3.1% |
| Backyard | 5.5% | 22.4% | 29.7% | 24.1% | 11.7% | 3.2% | 1.1% | 0.1% | 2.3% |
| Other Distance | 0.6% | 18.2% | 32.7% | 27.1% | 14.0% | 4.7% | 0.3% | 0.0% | 2.3% |
| Other Timed | 2.5% | 9.1% | 20.0% | 24.7% | 26.8% | 11.1% | 3.6% | 1.0% | 1.2% |
How Ultramarathon Demographics Compare to Overall Runners
Ultramarathons have some striking demographic differences compared to the average race. First, the gender gap is reversed (and amplified). While a small majority of overall race participants identify as female (53%), the opposite is true for ultramarathons, where 67% of runners identify as male.
Similarly, the age trends are different, with much of the gap due to the lack of children in ultramarathons. Ultra’s see much higher percentages of runners in their 30’s & 40’s (55% compared to 46%), as well as more runners continuing into their 50’s (15% vs 12%). On the flip side, runners 60+ stick around longer for shorter distance events.
TheUltramarathons vs All Events
Gender Distribution
Age Distribution
Takaway: There’s room to grow ultramarathons from the missing demographics. Actively market to women, and consider adding flexible options like timed events (where women are more likely to sign up). Flexibility may also help maintain ultramarathoner participation longer, with 50+ participants more often opting for a timed event over a set distance.
How Much Does an Ultramarathon Cost?
Somewhat predictably, race costs increase for longer distance events with longer staffing hours and more logistical overhead. The average 50K costs $117.33, while the average 100M comes in at $286.81. Timed races, which usually take place on looped courses with a smaller footprint, are more economical on average ($92-101).
The variability in pricing is large, and any individual race has to base their price on the costs of their specific event. Note that these are the average fees paid, and many races have both high and low cost tiers.
Average Race Fee
| Category | Average Fee |
|---|---|
| 50K | $117.33 |
| 50M | $172.95 |
| 100K | $208.73 |
| 100M | $286.81 |
| 6 Hour | $92.25 |
| 12 Hour | $101.06 |
| 24 Hour | $99.74 |
| Backyard | $89.17 |
| Other Distance | $150.60 |
| Other Timed | $142.78 |
How Early Do People Register for an Ultramarathon?
Understanding the registration patterns of races is key for budgeting and marketing. For the average ultramarathon, the majority of the field (91%) is set before race week. With the long training schedules, runners are more likely to register early, with 68% registering more than 2 months before race day.
However, that doesn’t mean people plan commit a year in advance. Just 7% of participants sign up more than 9 months prior to race day.
Timed events and Backyard events have the highest rate of procrastination, with 23% of 6-hour racers and 20% of Backyard participants registering on race week. This is likely because these events allow for flexibility to do as much (or little) as a participant wants, rather than committing to a full distance.
When Runners Register
| Category | Race Day | 1-7 Days | 8-14 Days | 15-30 Days | 31-60 Days | 61-90 Days | 91-120 Days | 121-150 Days | 151-180 Days | 181-210 Days | 211-240 Days | 241-270 Days | 271-300 Days | 301-330 Days | 331-365 Days | >365 Days |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 50K | 3.6% | 7.2% | 5.8% | 11.3% | 15.8% | 10.6% | 10.0% | 8.1% | 6.3% | 3.7% | 4.0% | 7.4% | 1.0% | 0.7% | 0.9% | 3.6% |
| 50M | 1.1% | 4.1% | 2.9% | 6.3% | 10.4% | 8.4% | 10.1% | 11.7% | 9.2% | 6.5% | 8.3% | 13.8% | 1.5% | 1.6% | 1.1% | 3.0% |
| 100K | 2.5% | 4.0% | 3.1% | 7.2% | 13.0% | 9.6% | 7.6% | 6.9% | 20.8% | 8.1% | 9.8% | 5.3% | 1.1% | 0.7% | 0.4% | 0.0% |
| 100M | 3.6% | 1.9% | 2.7% | 5.6% | 8.8% | 8.7% | 8.6% | 8.5% | 6.8% | 11.2% | 5.4% | 16.0% | 4.3% | 6.0% | 1.9% | 0.0% |
| 6 Hour | 8.3% | 14.6% | 6.7% | 11.9% | 12.8% | 14.5% | 13.6% | 5.5% | 2.2% | 0.9% | 8.4% | 0.2% | 0.1% | 0.0% | 0.0% | 0.3% |
| 12 Hour | 8.0% | 8.2% | 4.8% | 13.1% | 14.1% | 12.8% | 13.5% | 6.0% | 9.0% | 2.3% | 4.7% | 0.9% | 1.6% | 0.2% | 0.7% | 0.4% |
| 24 Hour | 3.2% | 3.6% | 1.9% | 6.8% | 8.1% | 5.0% | 7.0% | 4.1% | 3.5% | 4.0% | 14.5% | 30.5% | 1.7% | 3.7% | 2.4% | 0.0% |
| Backyard | 6.6% | 12.9% | 5.5% | 14.3% | 21.6% | 7.0% | 5.4% | 4.5% | 3.4% | 1.7% | 1.2% | 1.3% | 0.4% | 0.2% | 13.8% | 0.0% |
| Other Distance | 2.6% | 5.4% | 8.8% | 10.1% | 14.6% | 10.4% | 1.8% | 7.3% | 5.2% | 7.6% | 9.8% | 11.8% | 1.1% | 2.3% | 1.2% | 0.0% |
| Other Timed | 3.1% | 5.1% | 4.7% | 7.5% | 13.4% | 8.7% | 9.1% | 7.9% | 6.9% | 4.8% | 1.5% | 1.0% | 1.2% | 0.5% | 24.5% | 0.0% |
How Ultramarathon Registration Patterns Compare to All Races
Ultramarathoners are significantly more likely to register early than the average racer. 44% of all ultramarathoners sign up more than 4 months prior to race day, compared to just 9% for the average race. And that makes sense: many people can decide last minute to run a 5K, but may need to train for months to run 50 miles. Additionally, there are many fewer ultramarathons than 5K’s each week, meaning runners may also need to plan for travel.
Registration Timeline
Takeaway: Ultramarathon marketing timelines should be markedly different than most races. With 68% of ultra runners registering more than two months out (and 44% more than 4 months out), throw out your 5K-based marketing plan. Registration should open early, and early bird pricing should apply to 6-9 months out, not 3 months.
How Far Do People Travel for an Ultramarathon?
As noted, there simply aren’t that many ultramarathons (compared to the size of the country). Because of that, runners are willing to travel relatively long distances for the race distances they want. The further the race, the more likely the runner is traveling to get there. 46% of 50K runners are running in their relative backyard (within 50 miles), while just 13% of 100 milers are able to stay within 50 miles. Meanwhile, nearly half of 100 milers (49%), 38% of 100K runners, and 34% of all 50 milers travel more than 200 miles to their race. The sheer quantity of 50K races, compared to longer distances, likely drives this need to travel.
On the other hand, timed races and backyard events seem to appeal to more local racers, with the majority of participants traveling less than 50 miles.
Travel Distance
| Category | 0-20 Miles | 21-50 Miles | 51-100 Miles | 100-200 Miles | 200+ Miles |
|---|---|---|---|---|---|
| 50K | 21.9% | 23.5% | 19.8% | 15.1% | 19.8% |
| 50M | 11.9% | 18.0% | 20.2% | 15.6% | 34.3% |
| 100K | 10.3% | 13.8% | 19.6% | 18.4% | 38.0% |
| 100M | 4.1% | 8.7% | 11.8% | 26.1% | 49.4% |
| 6 Hour | 49.4% | 28.3% | 11.3% | 6.3% | 4.7% |
| 12 Hour | 46.5% | 23.6% | 14.5% | 6.9% | 8.5% |
| 24 Hour | 24.7% | 25.0% | 22.6% | 15.3% | 12.5% |
| Backyard | 44.1% | 24.7% | 14.1% | 8.5% | 8.6% |
| Other Distance | 18.0% | 14.9% | 17.1% | 21.4% | 28.6% |
| Other Timed | 13.0% | 25.0% | 20.8% | 20.4% | 20.8% |
Takeaways:
- Timed events have local appeal. With later registrations and more localized registrants, timed races are different from distance-based ultramarathons. Race directors looking to boost revenue for existing events with low overhead should consider adding a 6-hour race to an existing trail weekend to capture more local runners using the same course.
- Travel details are crucial for 100-milers. With nearly half of all 100 mile runners traveling more than 200 miles, race directors should provide as much information as possible regarding hotel/camping options, airport proximity, and travel options for crew. Make travel easy so runners can focus on running!
Are Ultramarathons Growing?
The final question we looked at is perhaps the most interesting: are ultramarathons growing? While we can’t answer the question of whether the sport is growing as a whole, we can see if the average ultramarathon race is seeing growth. To do that, we looked only at ultramarathons that were on RunSignup in both 2024 and 2025 to see if their average participation grew.
The good news? Yes, ultramarathons grew in 2025. In fact, they grew 6.5% on average, slightly more than we saw across all RunSignup races (average growth of 5%).
Do ultramarathons actually grow more when they actively use the RunSignup platform? The data suggest yes. When we filtered out ‘imported’ races – events that hosted registration on another platform, but imported their data to RunSignup for timing or results – the growth rate increased. Ultramarathons utilizing RunSignup for their registration grew by an impressive 8.3% in 2025.
Use caution drawing strong conclusions from the growth or decline of specific distances. Because ultramarathons are less common, the sample-size for any specific distance is small, and the significant success or struggle of one or two races could make a noticeable impact on the year-over-year average. If trends for specific distances continue for multiple years, it may provide more meaningful information.
Event Growth
| Category | Growth Rate |
|---|---|
| 50K | +8.6% |
| 50M | -4.8% |
| 100K | +16.6% |
| 100M | +9.5% |
| 6 Hour | -1.9% |
| 12 Hour | +10.8% |
| 24 Hour | +9.9% |
| Backyard | +17.2% |
| Other Distance | +24.4% |
| Other Timed | +29.7% |
The Fine Print: How We Used Our Data
This report is based on RunSignup race and participant data for 2025 events over 26.2 miles, including both paid and imported registrations. For specific reports, such as the pricing report, imported registrations were ignored. Distance traveled was based on zip code, not specific address; races that did not collect participant addresses were excluded from the travel distance report.