| HLCS | Hadley Luzerne Central School
| Others |
| HLCS | Hastings Landscape Conservation Services
| Others |
| HLCS | Head Lamp Cleaning System
| Others |
| HLCS | Healthy Lawn Care Services
| Others |
| HLCS | Historical Literary and
| Others |
| HLCS | Historical Literary and Cultural studies
| Others |
| HLCS | HoLoCarboxylase Synthetase
| Others |
| HLCS | Horned Lizard Conservation Society
| Others |
| HLCS | Horstmann Lynch Construction Services, LLC
| Others |
| HLCS | Houghton Lake Community Schools
| Others |
| HLCS | House of Legal Consultancy & Services, LTD.
| Others |
| HLCS | Hyrail Limits Compliance System
| Others |