Westlife are an Irish boy band, formed in 1998 in Sligo, Ireland. They disbanded in 2012 and reunited in 2018. They were originally signed by Simon Cowell in the UK, Clive Davis in the US and managed by Louis Walsh and Sonny Takhar. The group currently consists of Shane Filan, Markus Feehily, Kian Egan, and Nicky Byrne.
 
They have released eleven studio albums. Four as a five-piece and seven are as a four-piece. The group rose to fame with their debut international self-titled studio album, Westlife (1999). It was followed by Coast to Coast (2000), World of Our Own (2001), Unbreakable – The Greatest Hits Vol. 1 (2002), and Turnaround (2003), which continued the group's success worldwide. Before the start of their Turnaround Tour in 2004, one of the original members, Brian McFadden, departed from the band. The four remaining members continued as a group to release their cover albums Allow Us to Be Frank (2004) and The Love Album (2006) and the studio albums Face to Face (2005) and Back Home (2007). After a hiatus of studio recording for almost one year in 2008, they regrouped and released the studio albums Where We Are (2009), and Gravity (2010), and the compilation album Greatest Hits (2011). After eight years, the quartet group released their eleventh studio album, Spectrum, in 2019.
 
According to the British Phonographic Industry (BPI), Westlife has been certified for 13.1 million albums, 1.3 million video albums, and 10.4 million singles, with a total of more than 24 million combined sales in the UK. They are also currently ranked 19th with the most number-one albums of all time and sixth highest band in the list. The group have accumulated 14 number-one singles as a lead artist as well as having eight number-one albums in the United Kingdom, making them Ireland's most prolific chart-toppers. In 2012, the Official Charts Company listed Westlife 34th amongst the biggest-selling singles artist, 16th amongst the biggest selling groups, and 14th with most top ten hits all the highest for a boy band and a pop group in British music history. They are the biggest selling album group of the 2000s decade in the UK as well. Three of their studio albums were part of the 50 fastest selling albums of all time in the UK. The group have the most consecutive number-one studio albums in a decade in the UK and Ireland for a band since the Beatles and for a pop band and act since ABBA. Also in Ireland, they have 11 number-one albums with a total of 13 top two albums, 16 number-one singles as well as 34 top-fifty singles.