
Functional Martial Arts Training
Jiu Jitsu | Muay Thai | Boxing | MMA

Where Champions train champions
on and off the mats
Welcome to The Grindhouse! Thank you for your interest and for coming to learn more about our gym.
We are fortunate to have one of the greatest self-defense communities in Montana. From our kids program all the way to our competition team, our supportive culture and encouraging instructors have made our gym the best place to embark on your martial arts journey, no matter what your goals are.
OUR PROGRAMS
Training Schedule
Monday
12-2pm Open Mat
4-5pm Kid's No-Gi Jiu Jitsu
5-6pm Adult Gi Jiu Jitsu
6-7pm Boxing
7-8pm MMA/Muay Thai
Tuesday
12-2pm Open Mat
4-5pm Kids Gi Jiu Jitsu
5-6pm Adult Gi Jiu Jitsu
6-7pm Boxing
7-8pm Adult No-Gi Jiu Jitsu
Wednesday
12-2pm Open Mat
4-5pm Kids MMA Striking
5-6pm Adult Gi Jiu Jitsu
6-7pm Adult No-Gi Jiu Jitsu
7-8pm Muay Thai
Thursday
12-2pm Open Mat
5-6pm Adult No-Gi Jiu Jitsu
6-7pm Adult No-Gi Jiu Jitsu
7-8pm MMA
Friday - Sunday
12-2pm Open Mat
Will Grundhauser
meet your instructor
BUILDING THE GRINDHOUSE
Will Grudhauser is the founder and head coach of The Grindhouse in Billings, Montana. He is a 5th generation Montanan, a father & husband, and a U.S. Navy Veteran.
Will founded the Grindhouse over two decades ago, and has let his mission of helping students change their lives through martial arts direct his journey as a coach and leader.
Over the years at the Grindhouse, Will has completed his own successful MMA career and has led Grindhouse fighters to championships in MMA, jiu jitsu, and boxing across a wide range of fight promotions.
Will and his family continue to pour into the Grindhouse community by training with members, organizing world-class seminars, coaching athletes throughout their fight careers, and providing a space for people to find community and personal growth through training.
Competition background
3rd Degree BJJ Blackbelt
ADCC Masters World Champion
F2W Summer Classic Advanced Nogi Champion
Gracie World Gi Absolute 2nd Place
Cauliflower Ear Invitational Advanced No-Gi Champion
Grapplers Quest Advanced No Gi Champion
9x Grapplers Quest No-Gi Advanced Champion
7x Fight to Win National Champion
Fight to Win Pro Veteran
Fight to Win Gi blackbelt National Champion.
Fusion Fight League Welterweight Champion MMA
Fightforce MMA Welterweight Champion
Ultimate Showdown Welterweight MMA Champion
Undefeated Pro MMA Career
What Our Members
Have to Say
FREQUENTLY ASKED QUESTIONS
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Our kid's program starts at 4 years old, and there's no upper age limit to how long you can train (or start!).
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With our monthly membership you have access to every class on our schedule. You can hit open mat every day and take as many classes as you would like.
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We do! Many of our members also have children in the kids program, or siblings and partners that train with them. We have family packages for families with multiple students in our programs.
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Our classes are a mix of all skill levels. When you're first starting out, we'll often pair you with someone at your skill level for drilling and practicing. Many of our more experienced members take pride in helping out new members and they're always happy to come help with your technique!
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We have all of the equipment at the gym that you might need. We have vetted our favorite products, and have gi's, shorts, rash guards, gloves, shin pads, etc. that are available for sale at the gym.
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If you're doing no-gi or boxing, bring a mouthguard and athletic clothes to train in. Shorts with no pockets are recommended (to avoid getting toes, fingers, etc. caught in them). If you're doing gi jiu jitsu, we have some available at the front desk when you check in.
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We do! If you're traveling or can't commit to a full training schedule, we offer drop-in's to come train or attend open mat.

The hardest Part of Your journey is walking through the door.
Come try a free trial class and begin your martial arts journey!