"Birthday" is a song written and recorded by Icelandic band The Sugarcubes for their 1988 debut album Life's Too Good. It was their first international single and the first single released from the album. The Icelandic-language version "Ammæli" was released on the Iceland-only single Einn Moli' Á Mann (One Cube Per Head) the previous year and was included as the B-side on the international single.
After "Birthday" became the single of the week in Melody Maker magazine and NME in August 1987, and was selected as number one in John Peel's Festive Fifty list, the band attained worldwide recognition and success. In the United Kingdom, the song was the group's first chart entry at #65 and also reached number two on the country's indie charts. "Birthday" was ranked at number 15 on The Village Voice's "Pazz & Jop" critics' annual year-end poll to find the best music of 1988. The Sugarcubes performed the song, along with "Motorcrash" on Saturday Night Live during the October 15, 1988 episode, which was hosted by Matthew Broderick.
The song was remixed in 1988 by Jim and William Reid of The Jesus and Mary Chain and reissued as "Birthday (The Christmas Mixes)". Remixes by Justin Robertson and Tommy D were produced in 1992 for the compilation It's-It, and were also released as a single.