"Swear It Again" is a song by Irish boy band Westlife, released as the first single from their debut album Westlife. It peaked at number one in the UK Singles Chart for two weeks in May 1999. It moved to 182,000 units in the first two weeks of its release and spent 13 weeks on the charts. This made it the first of fourteen UK number-one singles. To date, it is Westlife's only single to have charted in the U.S., peaking at number 20 and number 75 on the Billboard Hot 100 Year End Chart in 2000.