Take That had eight Number Ones in the course of six years and Boyzone six over the same period of time, but Westlife notched up an amazing seven in their first year and a half of existence.
After winning six awards at the December 2000 Smash Hits Poll Winners Party, the Irish hunks can rightly lay claim to the title of Britain's biggest pop acts - but where did it all start?
Original band members Shane Filan, Kian Egan and Mark Feehily were born and grew up in the windy Irish west coast town of Sligo. In 1998, after success on local TV, Boyzone's manager Louis Walsh snapped then up and landed them a support slot in Dublin with boy band stalwarts The Backstreet Boys. For the gig the trio contracted two further singers, Dubliners Bryan McFadden and Nicky Byrne. Boyzone frontman Ronan Keating then stepped in to manage the band and help nurture its raw talent. In April 1999, Westlife's first single, Swear It Again, stormed into the top of the UK charts and since then there's been no looking back.
The boys held the Christmas 2000 number one spot with their version of Abba's hit I Have A Dream for four weeks. They then outsold the Spice Girls three times over with their new album Coast To Coast in November 2001. Rumours of a feud sprang up when Bryan dismissed the Spices' album Forever saying: "I've heard it, but I thought all the songs sounded the same." Mel C retorted on TV that she thought the boys were "talentless".
At the start of 2001 pop's best-kept secret was revealed when Bryan announced that he was to wed former Atomic Kitten singer Kerry Katona. It later emerged that the couple were expecting a child together - baby girl Molly was born on August 31, 2001 and second daughter Lilly Sue followed on February 5, 2003.
The other boys have also maintained fairly high profile romances. Nicky married Irish prime minister's daughter Georgina Ahern in August 2003 and Shane wed Gillian Walsh at the end of 2003.
Then on March 9, 2004 Westlife fans were left stunned after Bryan McFadden revealed that he was to leave the band, saying he wanted to spend more time with his wife Kerry and their two young children. His family break was short lived, however. His solo single shot to number one, and soon afterward, in October 2004, he announced he and his reality TV star wife were splitting up.
The rest of the group continued successfully as a four, before announcing their amicable split in October 2011.