NHK Kōhaku Uta Gassen , more commonly known simply as Kōhaku, is an annual New Year's Eve television special produced by Japanese public broadcaster NHK. It is broadcast live simultaneously on television and radio, nationally and internationally by the NHK network and by some overseas broadcasters who buy the program. The show ends shortly before midnight. Before the show began broadcasting on television in late 1953, the show was held on 3 January and only consisted of a radio broadcast.

Ōmisoka (大晦日) or ōtsugomori (大晦) is a Japanese traditional celebration on the last day of the year. Traditionally, it was held on the final day of the 12th lunar month. With Japan's switch to using the Gregorian calendar at the beginning of the Meiji era, it is now used on New Year's Eve to celebrate the new year.