List of UK Singles Chart Christmas number ones

In the United Kingdom, Christmas number ones are singles that are top of the UK Singles Chart in the week in which Christmas Day falls. Novelty songs, charity songs or songs with a Christmas theme have regularly been at the top of Christmas charts. Traditionally the volume of record sales in the UK peaks at Christmas, with the Christmas number one being considered especially prestigious, more so than any other time of year. Many of the Christmas number ones were also the best-selling song of the year. Due to the common practice of dating a chart by the date on which the week ends, the Christmas chart is dated the end of the week containing 25 December, but comprises sales for the week before that. The most recent Christmas number one single is "Rockabye" by Clean Bandit featuring Sean Paul and Anne-Marie.

The official UK Singles Chart began in 1952 after appearing in the New Musical Express; the positions of all songs are based on week end sale totals (from Sunday to Saturday until 2015, then from Friday to Thursday). Before 1987 they were released on a Tuesday due to the need for manual calculation. The emergence of a serious contest for the Christmas number-one spot began in 1973 when the band Slade deliberately released "Merry Xmas Everybody" as an effort to reach the top of the charts on Christmas.

Since 2002 the Christmas number one has been dominated by reality television contests, with the winners often heading straight to number one in the week before Christmas. This trend began when Popstars: The Rivals contestants released the top three singles on the Christmas chart. From 2005 to 2008, 2010 and 2013 to 2014, the winners of The X Factor took the number-one spot on seven occasions. In 2007, the X Factor single was so much of a prohibitive favourite for number one that bookmakers started taking bets on which song would be the "Christmas Number Two" instead.

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