Christmas number-one singles in the UK

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 glam rock bands Slade and Wizzard deliberately released festive songs in an effort to reach the top of the charts on Christmas, with Slade's "Merry Xmas Everybody" beating out Wizzard's "I Wish It Could Be Christmas Everyday" for the number one spot that Christmas.

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