NSL may refer to:
Government and politics
- National Security League, an American preparedness organization
- National Socialist League, a British pre–World War II Nazi group
- National Socialist League (United States), a gay neo-Nazi party in the U.S., 1974–1980s
- National Socialist Legion, an American neo-Nazi group
- National security letter, an administrative subpoena issued by the U.S. government
- National Security Act (South Korea)
- Hong Kong national security law
Sports
- Naša Sinalko Liga, a Serbian basketball league known as the Sinalco League
- National Soccer League (disambiguation)
- National Softball League, a British amateur co-ed slow pitch softball league
- Netball Superleague, a British netball league
- Northern Super League, a Canadian women's soccer league
- Nottinghamshire Senior League, an English association football league
Transportation
- NSL Buses, London, England
- North–South MRT line of the Singapore Mass Rapid Transit system
Languages
Other
- NSL Services Group, a business group in London, England
- Nanosphere lithography, a method to produce nanoscopic structures
- Nintendo Switch Lite
- Nuziveedu Seeds Limited