- Machine Shop Supplies
- Machine Shops
- Machine Tools
- Machinery Movers
- Machinery Repair
- Machinery Sales
- Magazine Advertising
- Magazine Distributors
- Maid Service
- Mailing Lists
- Major Appliance Stores
- Makeup Artists
- Management Consultants
- Manicures and Pedicures
- Mantels
- Maple Syrup
- Maps
- Marble
- Marijuana Retail
- Marine Equipment
- Marine Surveyors
- Marketing Agencies
- Martial Arts Schools
- Masons
- Massage Parlours
- Massage Therapists
- Massage Therapy Schools
- Material Handling Equipment
- Maternity Clothes
- Mats
- Mattresses
- Meat Packers
- Meat Wholesalers
- Mechanical Contractors
- Media Monitoring
- Medical Billing
- Medical Centres
- Medical Clinics
- Medical Information
- Medical Laboratories
- Medical Plans
- Medical Supplies
- Mediterranean Restaurants
- Mental Health Service
- Merchandise Warehouses
- Metal Doors
- Metal Finishers
- Metal Forming
- Metal Heat Treating
- Metal Specialties
- Metal Stamping
- Metal Stamps
- Metals
- Metaphysical Products and Services
- Mexican Restaurants
- Middle Eastern Restaurants
- Military Goods
- Millwork
- Millwrights
- Minerals
- Mirrors
- Missions
- Mobile Home Dealers
- Modelling Agencies
- Money Transfers
- Mortgage Brokers
- Mortgages
- Motorcycles
- Mould Makers
- Moving and Storage
- Mufflers
- Multimedia
- Municipal Government
- Museums
- Music Arrangers
- Music Lessons
- Music Publishers
- Music Stores
- Musical Instrument Stores
- Musicians
- Mutual Funds