- Mabton
- Machias
- Malden
- Malo
- Malone
- Malott
- Maltby
- Manchester
- Mansfield
- Manson
- Maple Falls
- Maple Heights-Lake Desire
- Maple Valley
- Maplewood
- Marblemount
- Marcus
- Marietta
- Marietta-Alderwood
- Markham
- Marlin
- Marrowstone
- Martha Lake
- Maryhill
- Marysville
- Mattawa
- May Creek
- McChord Air Force Base
- McCleary
- McKenna
- McMillin
- Mead
- Meadow Glade
- Meadowdale
- Medical Lake
- Medina
- Mercer Island
- Mesa
- Metaline
- Metaline Falls
- Methow
- Midland
- Mill Creek
- Mill Creek East
- Mill Plain
- Millwood
- Milton
- Mineral
- Minnehaha
- Mirrormont
- Mission Ridge
- Moclips
- Monroe
- Monroe North
- Montesano
- Morton
- Moses Lake
- Moses Lake North
- Mossyrock
- Mount Vernon
- Mount Vista
- Mountlake Terrace
- Moxee City
- Mt. Baker
- Mt. Spokane Ski and Snowboard Park
- Mukilteo
