The Brooks: Brooks Way
5AM: 5 After Midnight
Ottavio and Bradley: Bratavio
Viewers learned the new names at the end of Sunday night's episode, when the final twelve acts were rounded up for viewers.
Twins Kyle and Josh Brooks announced their name change on Twitter, saying they'd had to choose a different moniker for legal reasons.
They told fans: "We have big news! Due to legal reasons we've changed our band name to Brooks Way from The Brooks. We are really happy with this name… We hope you like the new name. We are Brooks Way."
5AM, meanwhile, just lengthened their name, pointing out the AM always stood for After Midnight. And Ottavio and Bradley's new name, Bratavio, is quite self-explanatory!
Of course, X Factor bands changing name is hardly a new thing. Who else remembers when Little Mix started life as Rhythmix? They had to change their name when they learned a charity called Rhythmix was already up and running.
Other bands to go though name changes include Kingsland, who switched to Kingsland Road, and Triple J, who became Union J.
Over the weekend, viewers watched the four judges - Louis, Nicole Scherzinger, Simon Cowell and Sharon Osbourne - choose which three acts they would bring through to live shows. Louis was joined by Fleur East and Alesha Dixon in Ibiza, Nicole welcomed Calvin Harris to Nice, Simon judged in Malibu with Emma Bunton and Mel B, and Sharon invited Robbie Williams to LA to help choose her top three artists.
5 After Midnight
The X Factor returns for the Live Shows Saturday at 8pm, ITV.