New Year's Eve is December 31, the final day of the Gregorian year, and the day before New Year's Day. New Year's Eve is a separate observance from the observance of New Year's Day. In 21st-century Western practice, the celebration involves partying until the moment of the transition of the year at midnight. Drinking champagne is also a major part of the festivities.

Within many cultures the use of fireworks and other noise making is a major part of the celebration in cities such as Berlin, New York City, Sydney, London, Paris, Rio de Janeiro, Toronto, Prague and Tokyo. New Year's Eve is a public non-working holiday in the following countries, among others: Australia, Argentina, Brazil, Mexico, Greece, New Zealand, the Philippines, and Venezuela.