"2 Become 1" is a pop ballad by English girl group Spice Girls. Written by the group members along with Matt Rowe and Richard Stannard during the group's first professional songwriting session, it was produced by Rowe and Stannard for the group's debut album Spice (1996). The lyrics focuses on the bonding of two lovers, and also address the importance of contraception. It was inspired by the special relationship that was developing between Geri Halliwell and Rowe during the writing session.
Released as the group's third single on 16 December 1996, it topped the UK Singles Chart for three weeks, becoming the group's third consecutive chart-topper, their second million-selling single, and their first Christmas number-one single in the United Kingdom.
"2 Become 1" was released in the United Kingdom, in three single versions. The first one, a maxi single that included the single version of the track, an orchestral take, the Junior Vasquez remix of "Wannabe", and "One of These Girls", a song written by the group with Paul Wilson and Andy Watkins—the songwriters and production duo known as Absolute. The second version was the special Christmas pack, a standard CD single in a cardboard case that included a signed postcard with a Christmas message from the group. This version contained the single version, the Dave Way remix, and their own version of Leroy Anderson's "Sleigh Ride". The third version was a two-track cassette single, featuring the single version and the orchestral take of the song.
It sold 209,000 copies in the first three days of release and 430,000 in the first week, becoming the tenth best-selling single of the year. "2 Become 1" sold 1.11 million copies in total, giving the Spice Girls their second and final million-selling single in the UK.
In Ireland, "2 Become 1" was the group's second number-one single, and their first to debut at the top of the Irish Singles Chart. It stayed at the top position for six weeks, and became their first Christmas number-one single in the country. It topped the singles chart in Spain, and peaked inside the top ten in Austria, Denmark, Finland, France, Italy, the Netherlands, Norway, Sweden and Switzerland, and inside the top fifteen in Belgium and Germany. It was also commercially successful in Australia and New Zealand, peaking inside the top three on both countries.
The song was released in the United States, in July 1997, peaking at number four on the Billboard Hot 100.