Organizers
- Maine Township
- Mainly Marathons
- Mainstream Promotions
- Maison T Ortiz Youth Outdoor Skills, Inc.
- Majestic View Nature Center
- Major Game LLC
- Major Garrett Knowlan Memorial Fund
- Major Paul C. Voelke Memorial Scholarship Fund
- Major Taylor Dayton Cycling Club
- Make Wishes Come True 5K Run/Walk
- Make-A-Wish UK
- Makefield Highlands Golf Club
- Maker Lab Extreme
- Maker Youth Foundation
- MakerKids
- Maketewah Country Club
- Makin Macon Fit
- Making Strides against Breast Cancer - VT
- Making Waves Aquatics Club
- Malaga Camp
- Malden PWFA
- Malibu Race Series
- Malibu Soccer Academy
- Malibu Swim Camp
- Malibu Triathlon Productions, LLC
- Malibu Water Polo Camp
- Malibu Water Polo Camps
- MaliVai Washington Kids Foundation Youth Center
- Mallard Cove Golf Course
- Malone Golf Club
- Maltby PONY Baseball
- Malungs OK
- Mama Bootcamp
- Mama Bootcamp, Inc.
- Mammoth Events
- Mammoth Mountain Community Foundation
- Mammoth Mountain Ski Area, LLC
- Mammoth Track Club
- Man O' War Golf
- Manchester Athletic Association (St. Louis)
- Manchester Essex Little League
- Manchester Family Golf Center
- Manchester Little League
- Manchester Maple Leaf Half Marathon & Kotler 5K
- Manchester Racquet Club
- manchester Recreation Complex
- Manchester Sailing Association
- Manchester Youth Football League
- Mandaville Camp & Retreat Center
- Mandaville Camp and Retreat Center