The 29-year-old Brazil international is due to arrive in the UK on Thursday night to undergo a medical and finalise personal terms.
Carlos has spent the last three years with Sevilla and was part of the team which won the Europa League in 2020, beating Wolves in the quarter-final.
Villa boss Steven Gerrard was eager to strengthen his defence and the signing of Carlos, a target for Newcastle during the January window, represents another statement of intent.
The centre-back will be their second signing since the end of the Premier League season, following the acquisition of Marseille midfielder Boubacar Kamara. A £17.2m deal to sign Philippe Coutinho from Barcelona was agreed earlier in the month.
Gerrard still wants to add a left-back and potentially a striker but Villa will also look to move some fringe players out. Douglas Luiz, who has just one year remaining on his contract, is a target for Roma while offers will be considered for Morgan Sanson, Anwar El Ghazi and Trezeguet among others.
Assistant boss Michael Beale has, meanwhile emerged as a candidate for QPR’s vacant managerial post.
The Championship club are thought to have approached Villa and requested to speak with the 41-year-old as they hunt a replacement for Mark Warburton, who left his role as boss earlier this month.
London-born Beale is a highly-rated coach and was recent linked with the vacant post at Charlton, now set to be taken by former Albion coach Ben Garner.
But he is also an important member of Villa’s backroom team and though Gerrard won’t stand in the way of a staff member who wants to move on, he will be eager for Beale to remain on board as he looks to improve the club’s fortunes.