NSC is a three-letter acronym (TLA) that may refer to:
- National Safety Council, an American nonprofit organization
- National Salvation Committee, a Ukrainian organization founded during the Orange Revolution
- National Scrabble Championship, the largest Scrabble competition in the U.S.
- National Security Council, a type of government agency, found in many countries:
- National Security Council (India)
- Israeli National Security Council
- National Security Council of Pakistan
- National Security Council (Turkey)
- United States National Security Council
- National Security Cutter, a United States Coast Guard ship
- National Semiconductor Corporation, American semiconductor manufacturer
- National Senior Certificate, the equivalent of a high school diploma and the school-leaving certificate in South Africa
- National Skin Centre, a government-run specialised medical facility in Singapore
- National Software Centre
- National Sort Code, the bank code used in Ireland.
- National Space Centre, a British tourist attraction devoted to space science and astronomy
- National Sports Center, "The World's Largest Amateur Sports Facility" in Blaine, Minnesota, USA
- National Sports Centre (Isle of Man), a large multi-sports centre and athletics in Douglas, Isle of Man
- National Statistical Commission, an Indian organisation aiming to improve data collection
- necessary and sufficient condition, in logic and mathematics
- Nepean Sailing Club, an active sailing club in the Ottawa area
- Netscape Communicator, an internet suite produced by Netscape Communications Corporation
- NetShow Channel, the old name of Windows Media Station
- Network SouthCentral, an independent train operating company
- Network Systems Corporation, an early manufacturer of high-performance computer networking products
- Neural Stem Cell, the self-renewing, multipotent cells that generate the main phenotypes of the nervous system
- Nevada State College, a state college in Nevada
- New Safe Confinement, the structure intended to contain the nuclear reactor at Chernobyl, Ukraine, part of which was destroyed by a catastrophic nuclear accident in 1986
- Nomura Securities Co., a subsidiary of the Japanese Nomura Group
- NonStop Clusters, an add-on package for SCO UnixWare
- Norfolk Southern Railway, a major railway company
- North-South Carrier, a water pipeline in Botswana
- North Star Conference, a women's college sports conference in the NCAA
- Northern Southland College, a secondary School in Lumsden, New Zealand
- Norwegian Space Centre (Norwegian: Norsk Romsenter), a Norwegian government agency that promotes space exploration
- No-Slot Clock, a chip-like device that could be used directly in any Apple II computer
- Nouveau Système de Cotation, an electronic trading technology created by Euronext
- NSC United, an American soccer team based in Minnesota
- Nursing Service Cross (Australia), a decoration (medal) of the Australian Honours System
- National Science Council, the main governmental promotion and funding body for science research in Taiwan, Republic of China