"London Boy" is a song by the American singer-songwriter Taylor Swift from her seventh studio album, Lover (2019). Swift, Jack Antonoff, and Sounwave (Mark Anthony Spears) wrote the song; the first two are credited as producers while Sounwave is credited as co-producer. A reggae-influenced bubblegum pop song, "London Boy" includes a spoken-word intro by the English actor Idris Elba and contains an interpolation of the song "Cold War" by the American singer Cautious Clay, who was given a co-writing credit on the track. Inspired by Swift's experiences in London, the lyrics mention various London locations and express a Tennessean woman's infatuation with a male love interest from the city. "London Boy" charted in Australia, Canada, Singapore, and the United States, and it received a silver certification in the United Kingdom. Music critics gave "London Boy" mixed reviews. Those complimentary found the production upbeat and catchy, but those critical deemed the lyrics unsophisticated. The British press generally panned the song and thought that the lyrics were a poor representation of London. During promotion of Lover in 2019, Swift performed "London Boy" live on BBC Radio 1's Live Lounge and at Capital FM's Jingle Bell Ball.