| Maciag Offroad |  | | Leipzig | 11 |
| MacQueen's Bike Shop | | PE | Charlottetown | 24 |
| Mad Elk Cycles | | | | 24 |
| Malatestas Bikes | | | | 1 |
| Maros Bike | | | Cluj-Napoca | 1 |
| Martin's Bicycle Shop | | ON | Southampton | 16 |
| Marty's Mountian Cycle | | BC | Victoria | 93 |
| MEC (Mountain Equipment Co-op) Montréal | | QC | Montreal | 1 |
| Mellow Velo | | NM | Santa Fe | 7 |
| Messier Bicyclettes | | QC | Saint-Jean-sur-Richelieu | 11 |
| Metal Motion Bikes | | | Witten | 3 |
| Middle of Town Cycling | | KY | Louisville | 1 |
| Middletown Cycling | | KY | Louisville | 3 |
| Mikes Hike And Bike | | KY | Richmond | 6 |
| Mitchell Cycles | | | Swindon | 13 |
| MK Bikes | | | Karlsruhe | 2 |
| Moment Bicycles - Carmel Valley | | CA | San Diego | 1 |
| Monbike | | | Ponta Delgada | 32 |
| Monster Bike | | | Inverness | 22 |
| Monsterbike | | | Inverness | 16 |
| Mountain Mania Cycles - Carterton | | | Carterton | 2 |
| Mountain Mania Cycles - Didcot | | | Didcot | 2 |
| Mountain Mania Cycles - Goring | | | Reading | 2 |
| Mountain Mania Cycles - Tring | | | Tring | 5 |
| Mountain Trax | | | Wokingham | 20 |
| MountainBikeShop | | | Helsinki | 1 |
| MTB Connection | | NB | Lakeville | 2 |
| Mtb.lv Bicycle Workshop | | | Riga | 5 |
| Mud Sweat & Gears | | AB | Red Deer | 10 |
| Mud, Sweat, and Gears | | AB | Spruce Grove | 13 |
| Multibike | | | Concepcion | 20 |