- Ice Cream
- Ice cream production
- Ice Rink and Skating Arena Management
- Illustration
- Immigration policy
- Immigration Services
- Immunological Research and Development
- Import/Export of ice cream
- Impression die forging
- In-Home Care Service Providers
- Inbound/Outbound Sales
- Incineration of Non-Hazardous Waste
- Independent Contractors/Brokers
- Individual and Family Services
- Individual Sports Clubs
- Indoor Sports Facilities Operation
- Industrial Architects
- Industrial Building Cleaning
- Industrial design
- Industrial Electrical Power System Maintenance and Repairs
- Industrial equipment maintenance
- Industrial gas manufacturing
- Industrial Hardware
- Industrial hazardous waste management
- Industrial Machinery and Equipment Wholesalers
- Industrial Machinery Maintenance and Servicing of Motors
- Industrial Mechanics and Maintenance Technologies
- Industrial Plant Construction
- Industrial Process Improvement Services
- Industrial Roofing
- Industrial Sewing Machines
- Industrial staffing services
- Industrial and Warehouse Property Lettings
- Industrial Water Project Construction
- Infant and Toddler Care
- Infant Day Care
- Information Technology Consulting
- Infrastructure Construction
- Inland Waterway Transport Consultants
- Innovation and Invention in Engineering
- Inpatient Psychiatric Facilities
- Inpatient Rehabilitation Facilities
- Install and Repair Cabinetry & Furniture
- Installation of Central Heating Radiators
- Installation of electrical and electronic motor vehicle equipment
- Installation of Electrical Equipment for Utility Projects
- Installation of industrial refrigeration equipment
- Installation and Maintenance of Building Stone
- Installation and Maintenance of Nuclear Reactors
- Installation of Air Conditioning Systems
- Installation of industrial freezing equipment
- Installation of machinery in industrial plants
- Installation of Roof Coverings
- Installation of security systems
- Installation of Ventilation Systems
- Installation of plumbing systems and electrical systems in buildings
- Installation and Repair of Roof Framing
- Installation services for ceramic tiles and flags
- Installation services for hearing aids
- Installation of Telecommunication Equipment for Utility Projects
- Institutional Architects
- Institutional Buildings
- Institutional Catering
- Institutional and Industrial Power Supply
- Instructional Design Services
- Insulation Installation Services
- Insulation Services
- Insurance law advice
- Insurance underwriting and intermediation services
- Insurance Underwriting Services
- Intelligence Analysis and Surveillance
- Intercity Rail Transport
- Interior design and decorating
- Interior Designers/Decorators
- Interior furnishing of vessels
- Intermodal freight transport services
- Internal Medicine
- International Development Agencies
- International Film Distribution
- International Freight Air Transport
- International Freight Forwarding Services
- International passenger air transport
- International scheduled passenger air transport
- International Shipping Services
- Internet access provider services
- Internet publishing and broadcasting
- Internet Radio Broadcasting
- Internet Service Providers (ISP) Management
- Interpreter Services
- Inventory Management Services
- Inventory Management Solutions
- Investigation and security-related activities
- Investment Activities
- Investment Advice and Financial Planning Services
- Investment advice and portfolio management
- Investment and Asset Management Services
- Investment banking activities
- Investment banking services for property unit trusts
- Investment Banks
- Investment Casting Process
- Investment Firms and Brokerages
- Investment Holding Companies
- Investment management services
- Investment Properties
- Investment research services
- Investment Trust Administration
- Iron Ore Mining
- Irrigation Design and Implementation
- Irrigation Services
- Irrigation & Sprinkler System Rental
- Irrigation System Installation and Repair
- Irrigation System Maintenance & Installation
- Irrigation Systems
- IT Audit Services
- Information technology (IT) and business process outsourcing (BPO) advisory services
- IT Consultancy Services
- Information Technology (IT) Consulting
- IT Project Management
- Installation, maintenance, and repair of residential and commercial propane systems