- Canvas & Related Products, West Sayville
- Casual Dining Restaurants, West Sayville
- Caterers Food Services, West Sayville
- Christian Churches, West Sayville
- City & County Administrative Agencies, West Sayville
- City & County Government, West Sayville
- CNC Machine Shop, West Sayville
- Colleges & Universities, West Sayville
- Community Services, West Sayville
- Computer & Audio Visual Services, West Sayville
|
- Computer & Laptop Repair, West Sayville - PC Repair Services
- Computer & Software Stores, West Sayville
- Computer Repair, West Sayville
- Computer Software & Services, West Sayville
- Computer Software Service, West Sayville
- Construction, West Sayville
- Consultants & Services, West Sayville
- Cremation Services, Supplies & Equipment, West Sayville
- Cutting & Slitting Service, West Sayville
|
