"Fairytale of New York" is a song written by Jem Finer and Shane MacGowan and first released as a single on 23 November 1987 by their band The Pogues, featuring singer-songwriter Kirsty MacColl on vocals. The song was written as a duet, with the Pogues' singer MacGowan taking the role of the male character and MacColl the female character. It is an Irish folk-style ballad, and featured on The Pogues' 1988 album If I Should Fall from Grace with God.

Originally begun in 1985, the song had a troubled two year development history, undergoing rewrites and aborted attempts at recording, and losing its original female vocalist along the way, before finally being completed in summer 1987. Although the single never reached the coveted UK Christmas number one, being kept at number two on its original release in 1987 by the Pet Shop Boys' cover version of "Always on My Mind", it has proved enduringly popular with both music critics and the public: to date the song has reached the UK Top 20 on thirteen separate occasions since its original release in 1987, including every year since 2005, and was certified platinum in the UK in 2013. The song has sold 1.18 million copies in the UK as of November 2015. In the UK it is the most-played Christmas song of the 21st century. "Fairytale of New York" has been cited as the best Christmas song of all time in various television, radio and magazine related polls in the UK and Ireland.

Although there is agreement among the band that "Fairytale of New York" was first written in 1985, the origins of the song are disputed: MacGowan insisted that it arose as a result of a wager made by The Pogues' producer at the time, Elvis Costello, that the band would not be able to write a Christmas hit single; The Pogues' manager Frank Murray has stated that it was originally his idea that the band should try and write a Christmas song as he thought it would be "interesting". It was banjo player Finer who came up with the melody and the original concept for the song, which involved a sailor looking out over the ocean. Finer's wife Marcia did not like the original story, and suggested new lyrics regarding a conversation between a couple at Christmas. Finer told NME, "I had written two songs complete with tunes, one had a good tune and crap lyrics, the other had the idea for 'Fairytale' but the tune was poxy, I gave them both to Shane and he gave it a Broadway melody, and there it was".

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