The band's debut track 'Can We Dance' has topped the midweek chart update and is currently 13,000 copies ahead of its nearest competitor OneRepublic's 'Counting Stars'.
Jason Derulo's 'Talk Dirty' slips from the top spot to three, Katy Perry's 'Roar' is at four and Chase & Status are new at five with 'Count On Me'.
Nelly, Nicki Minaj and Pharrell Williams land at 16 with new single 'Get Like Me', while former X Factor contestant Lucy Spraggan returns to the Top 20 with a new version of 'Last Night (Beer Fear)' at 19.
Two Door Cinema Club are at 24 with 'Changing Of The Seasons', while Emeli Sandé's 'Clown' rises to 37 after an X Factor outing at the weekend.
Justin Timberlake is on course to claim his second UK number one album of 2013 with The 20/20 Experience - 2 of 2.
However, the US star's new collection is just 700 copies ahead of Haim's debut album Days Are Gone at number two.
Kings of Leon fall to three with Mechanical Bull, Alter Bridge are at four with Fortress and Arctic Monkeys are at five with AM.
Dizzee Rascal lands at nine with his new album The Fifth, while Sub Focus follows at 10 with Torus.
Timberlake's The 20/20 Experience: The Complete Experience - which collects both of his 2013 albums - is at 17, while Moby starts at 21 with Innocents.
Watch the music video for The Vamps' debut single 'Can We Dance' below: