- Machine Shop Supplies
- Magazine Advertising
- Magazine Distributors
- Mailing Lists
- Major Appliance Stores
- Marine Surveyors
- Masons
- Massage Therapists
- Mechanical Contractors
- Media Monitoring
- Medical Centres
- Medical Clinics
- Medical Information
- Medical Laboratories
- Mediterranean Restaurants
- Mental Health Service
- Merchandise Warehouses
- Metal Buildings
- Metal Finishers
- Metal Forming
- Metal Specialties
- Metal Stamping
- Metal Stamps
- Mexican Restaurants
- Middle Eastern Restaurants
- Military Goods
- Millwrights
- Minerals
- Mobile Home Dealers
- Modelling Agencies
- Mortgages
- Motorcycles
- Mould Removal
- Moving and Storage
- Mufflers
- Municipal Government
- Music Publishers
- Musicians
- Mutual Funds