Registration

• Race bib
• Race t-shirt
• Access to aid stations
• Final and intermediate timing
• Medical assistance
• Finisher medal
• Post-race food

Withdrawal Information: This registration is non-refundable and non-transferable. All deferral requests will be honored until March 11, 2026. To submit a deferral request, please contact  desertrats@service.byutmb.world.

• Runners who register within 50 days prior to Race Day will not have race materials personalized (name on merchandise apparel and name on race bib).
• Runners must be at least 18 years old to participate in the 100k and 50k, 16 years old to participate in the 21k, and 12 years old to participate in the 10k.
• Online Registration Closes: Sunday, April 5, 2026, at 11:59 pm PT or until the races are sold out.
• We will take onsite registrations at the expo for any open distances. There is NO RACE DAY REGISTRATION.
• Distance changes are subject to availability. Please reach out to the event inbox to inquire.
• Distance change requests can be made via email up to 45 days prior to the event. After the 45-day deadline, all distance changes must be completed at the event expo when picking up your bib. There are no distance changes on race day.
• Reference the REGISTRATION INCLUDES section on this page for the withdrawal policy.
• For questions, please reach out to desertrats@service.byutmb.world.

UTMB strongly believes in equal rights and opportunities for all members of the trail-running community. We are in the process of building inclusion and diversity policies on gender, race, age, social class and more. We endeavour to grow and continue to evolve the sport and to make UTMB World Series welcoming for each athlete.

You will automatically receive a confirmation email upon completing your registration.

Your age group category for the event you registered for will be reflective of your age as of December 31 of the event year.

Your name, and the names of other starters, is searchable via The Runner Start List or on UTMB Live prior to your race.

Online registrations are synced to our database within 24 hours. You can login to check your registration status, below:

Desert Rats Trail Running Festival by UTMB is the start towards your quest to the UTMB World Series Finals in Chamonix, the mythic UTMB Mont Blanc, the holy grail of trail running in the heart of the Alps, set on the three key distances: OCC (50K), CCC® (100K) and UTMB® (100M), the pinnacle trail running event.

As a UTMB World Series Event, the Top 3 female and Top 3 male runners of the 100K and 50K at Desert Rats Trail Running Festival gain automatic qualification to the CCC or OCC races, respectively.

All finishers of the Desert Rats Trail Running Festival by UTMB collect Running Stones that can be applied to the UTMB Mont-Blanc draw. To be eligible for the lottery, runners need to have a least one Running Stone and a valid UTMB Index.