Hogmanay is the Scots word for the last day of the old year and is synonymous with the celebration of the New Year in the Scottish manner. It is normally followed by further celebration on the morning of New Year's Day and, in some cases, 2 January—a Scottish bank holiday. In a few contexts, the word Hogmanay is used more loosely to describe the entire period consisting of the last few days of the old year and the first few days of the new year. For instance, not all events held under the banner of Edinburgh's Hogmanay take place on 31 December.

In the Gregorian calendar, New Year's Day is the first day of the calendar year, 1 January. Most solar calendars begin the year regularly at or near the northern winter solstice, while cultures and religions that observe a lunisolar or lunar calendar celebrate their Lunar New Year at less fixed points relative to the solar year.