Category I
- Ice Cream Cones or Wafers Manufacturing
- Ice Cream Manufacturing
- Ice Cream Store
- Ice Manufacturing
- Immunologist
- Import and Export Documentation Preparation Service
- Importers And Imported Items
- Importing And Export Agents And Merchants
- Indoor Plant Hire
- Industrial Ceramics Manufacturing
- Industrial Chemical
- Industrial Containers Manufacturing
- Industrial Equipment Training
- Industrial Fans Wholesale
- Industrial Furnaces Manufacturing
- Industrial Gas Manufacturing
- Industrial Ironing or Pressing and Laundry Machinery Manufacturing
- Industrial Laundry Equipment Wholesaling
- Industrial Machinery and Equipment Manufacturing
- Industrial Ovens Manufacturing
- Industrial Research Institution
- Industrial Saws Manufacturing
- Industrial Sewing Machines Manufacturing
- Industrial Waste Collection And Disposal Service
- Industrial Water Treatment Equipment Manufacturing
- Infants' Clothing Manufacturing
- Infectious Diseases
- Infertility Services Specialist Including IVF
- Information Storage And Retrieval
- Ink And Toner Cartridges
- Ink Manufacturing
- Inner Spring Mattress Manufacturing
- Inorganic Industrial Chemical Manufacturing
- Insecticide Manufacturing
- Installation Trade Services
- Insulation Glass Fibre or Mineral Wool Manufacturing
- Insulation Materials Installation
- Insurance Services
- Intensive Care
- Interior Decorating Service
- Interior Designers
- International Sea Transport and Services
- Internet Cafe
- Internet Publishing
- Internet Service Providers
- Internet Services
- Interpreting and Translating Service
- Investment Association
- Investment Company
- Investment Services
- IR or UV Lamp Manufacturing
- Iron and Steel Manufacturing
- Iron Ore Mining
- Iron Pyrite Mining
- Irrigation Systems Construction
