Merc may refer to:
- Mandatory employment-related costs, in Canada these are CPP, EI, and WC
- Merc Clothing, classic British clothing brand
- Merc MUD multi-user-daemon, a computer program for interactive communication
- Mobile Emission Reduction Credit (MERC), used in pollution reduction
- Middle East Rally Championship
Merc as an abbreviation:
- Chicago Mercantile Exchange, or the building where it operates, the Chicago Mercantile Exchange Center
- Materials and Energy Research Center, Iran, Tehran, Karaj, Meshkin dasht
- Mercantile National Bank Building, a building in Downtown Dallas
- Mercedes-Benz, a motor manufacturer and its products
- Mercenary, a soldier for hire
- Mercury automobile
- Mineral Exploration Research Centre, a geological research centre at Laurentian University
- San Jose Mercury News, a newspaper
- Sir Peter Blake Marine Education and Recreation Centre, an outdoor leisure complex in New Zealand
- Maharashtra Electricity Regulatory Commission, is Electricity regulatory commission in Maharashtra, India.