NK may refer to: Businesses Imerys, a French mining multinational (Euronext ticker:NK) Nordiska Kompaniet, a Swedish department store Northrup-King Seed Company, U.S. Spirit Airlines, U.S. (IATA:NK) NK.pl, a Polish social network (2006–2021)
Organisations Neturei Karta, a group of anti-zionist orthodox Jews Nippon Kaiji Kyokai, a ship classification society NK (), a name suffix for Croatian and Slovenian football clubs
Places North Korea, a country in Asia Nagorno-Karabakh Republic, a de facto state (1991–2023) Nikšić, Montenegro (license plate:NK) North Kingstown, Rhode Island, U.S. North Kingstown High School Nasik Road railway station (station code: NK), Maharashtra, India
Other uses NK (singer), a Ukrainian singer Naik (military rank), in certain South Asian armies Natural killer cell, in medicine Neue Kerze ('new candle'; nk), original name for the photometric unit the candela Norwegian krone, a currency Normal Country (, NK), a Polish right-wing political party