The Spaniard arrives at the Tottenham Hotspur Stadium on a deal expected to be worth just shy of £28million.
Reguilon joins on a five-year deal, taking the number 3 shirt, and he has been followed by former Real teammate Gareth Bale.
Fans have been reacting to Reguilon’s arrival on social media following the announcement of the deal.
Here’s what Spurs fans have had to say on Twitter.
Reguilon only ever made 14 league appearances for Real Madrid, graduating for the first team in 2018.
He was then loaned out to Sevilla for last season where he made 31 league appearances and won the Europa League.
Reguilon, a Spain international, now links up with Spurs, strengthening Jose Mourinho’s defence and slotting into left-back.
Bale has also completed his move, joining from Real Madrid on a loan deal until the end of the season with an option of a further season.
Spurs are expected to pay around 40% of Bale’s wages.