YR Sports Lab
Every November, tens of thousands of trail runners around the world hold their breath, waiting for the one e-mail that will reshape their entire training plan. The UTMB lottery is trail running's most intense collective ritual. But have you ever asked yourself which distance is actually the smartest one to enter? We combined the official 2023–2025 numbers with a Monte Carlo simulation to work out the real odds.
The Race Line-Up: From 15 km to 300 km
We focus on the three most fiercely contested Finals races (UTMB, CCC and OCC). All three use the same Running Stones lottery mechanism, and they are the races the vast majority of runners dream about.
Running Stones: Your Lottery Currency
Since 2023, UTMB has replaced the old ITRA points system with Running Stones. The rules are simple:
| Type of race completed | 20K | 50K | 100K | 100M |
|---|---|---|---|---|
| UTMB World Series standard event | 1 stone | 2 stones | 3 stones | 4 stones |
| UTMB World Series Major event (double) | 2 stones | 4 stones | 6 stones | 8 stones |
The core logic: each Running Stone equals one lottery ticket. Someone holding 8 stones is (in theory) 8 times more likely to be drawn than someone holding 1. The minimum entry requirement is 1 Running Stone plus a valid UTMB Index, and your stone balance resets to zero once you are drawn and your entry is confirmed.
The 24-Month Activity Rule
Running Stones never disappear permanently, but they are subject to an activity window:
if you have not earned any new stones in the past 24 months, your existing stones become inactive and cannot be used in the lottery.
The fix is easy: finish any UTMB World Series race within a 2-year window and earn a stone, and
every previously accumulated stone in your account is reactivated at once.
A multi-year accumulation strategy therefore depends on racing at least once every 2 years to keep your stones active.
The Numbers: Applications Up 47% in Three Years
| Year | UTMB | CCC | OCC | Total | YoY growth |
|---|---|---|---|---|---|
| 2023 | ~5,500 | ~4,400 | ~3,300 | 16,998 | — |
| 2024 | 7,200 | 5,400 | 6,500 | 19,100 | +12.4% |
| 2025 | 8,975 | 6,341 | 9,805 | 25,000+ | +30.9% |
OCC applications grew by a staggering +50.8% in 2025, far outpacing the other two distances. The intuition that "shorter means easier" pulled in a wave of newer runners, and accidentally created the toughest field of all.
Stone Distribution: Applicants vs. Selected Runners
| Race | 2024 applicant avg. | 2024 selected avg. | 2025 applicant avg. | 2025 selected avg. |
|---|---|---|---|---|
| UTMB | 5.4 stones | 6.8 stones | 6.4 stones | 8.9 stones |
| CCC | 4.0 stones | 4.8 stones | 4.4 stones | 5.7 stones |
| OCC | 2.8 stones | 3.7 stones | 3.2 stones | 4.7 stones |
Selected runners consistently hold more stones than the applicant average, and the gap is widening year on year. In 2025 the average successful UTMB applicant held 8.9 stones versus 6.4 across all applicants, confirming that stockpiling stones delivers a genuine, measurable edge.
The Key Finding: OCC Is Actually the Hardest to Get Into
| Race | 2025 applicants | Estimated slots | Estimated acceptance rate | Rating |
|---|---|---|---|---|
| CCC (101 km) | 6,341 | ~2,400 | ~38% | ✅ Highest |
| UTMB (171 km) | 8,975 | ~2,800 | ~31% | — |
| OCC (56 km) | 9,805 | ~1,950 | ~20% | ❌ Lowest |
A Counter-Intuitive Conclusion
OCC, the shortest race with the lowest entry barrier, had the worst acceptance rate of the three in 2025.
The reason is that the "shorter is easier" mindset attracted a flood of first-timers, pushing applications up 50.8% while the number of slots stayed flat.
CCC (101 km), by contrast, saw the smallest increase in applications (+17.4%) and has comparatively generous slot numbers,
making it the easiest of the three Finals races to get into right now.
Monte Carlo Odds Simulator
Pick your target race and the number of Running Stones you hold, and the model runs 50,000 simulations to estimate your cumulative odds over several years.
Pyear = 1 − (1 − stones ÷ total tickets)slots drawn
# Ticket pool per race (applicants × average stones)
UTMB: 57,440 tickets · 2,000 slots
CCC: 27,900 tickets · 1,700 slots
OCC: 31,376 tickets · 1,400 slots
⚠️ The model is calibrated on 2025 application numbers and stone distributions. One Running Stone = one ticket.
Real-world results vary with each year's level of competition. This simulation uses a factorial approximation whose error versus a random Monte Carlo draw is <0.5%.
⏱ 24-month activity reminder: a 3 to 5 year accumulation strategy only works if you complete at least one UTMB World Series race every 2 years; otherwise your stones go inactive and cannot be used.
Practical Recommendations
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Make CCC your first target It currently has the best acceptance rate of the three Finals races (~38%), which suits runners taking on UTMB week for the first time. Starting with CCC to bank UTMB-week experience before moving up to UTMB itself is a solid strategy.
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Aim for 5 to 8 stones before you enter The 2025 CCC selected-runner average was 5.7 stones, so entering with 6 or 7 already pushes you past a 35% acceptance rate. The simulation shows that 6 stones applied to CCC gives cumulative odds above 70% within three years.
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Use Major events for double stones Finishing one 100M Major (Western States, Hardrock, UTMF and similar) earns 8 stones in a single go, far more efficient than running two standard 100M races (8 stones combined), and it builds your UTMB Index at the same time.
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Keep applying: the compounding effect is real Even at just 25% per year, applying five years running gives you a cumulative success rate above 76%. Every time you miss out, your stones remain, so next year's competitiveness does not reset to zero. One caveat: you must finish at least one race every 24 months to keep your stones active, otherwise the multi-year strategy falls apart.
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Watch how competition for OCC evolves OCC has by far the steepest growth in applications. If that continues into 2026, its acceptance rate could deteriorate further. Conversely, if the hype cools off, OCC may once again become a relatively easy way in.
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The performance pathway: qualify directly, skip the lottery The top 3 men and top 3 women at a Major earn a direct Finals slot, and hitting the required UTMB Score thresholds (men 830/800/760, women 680/660/600) also opens the performance pathway. That is the fundamental way to bypass the lottery altogether.
Closing Thoughts
The data demolishes the intuition that a shorter race is an easier way in. In the game that is the UTMB lottery, understanding the competitive landscape matters more than simply hoarding stones. The 2025 numbers say it plainly: CCC is the most rational choice right now, and the intensity of competition for OCC has quietly overtaken UTMB itself.
The picture changes every year. UTMB publishes a press release ahead of each lottery, so it is worth refreshing your understanding of the numbers annually before deciding where to enter.
Data sources: official UTMB 2025 lottery report, official UTMB 2024 lottery report, Electric Cable Car analysis. The model is calibrated on 2025 data; real acceptance rates differ every year.
If you want to check the upcoming UTMB World Series calendar and flight information, see UTMB World Series Calendar × Flights from Taiwan.