The biggest transfers in the world in the 2026 January transfer window

The top three deals so far are Premier League signings, but Lazio have done some savvy business, even if their manager has never heard of their new striker…

The January window is open and some clubs wasted no time in strengthening their ranks.

Here are the biggest transfers in the world in January 2026…

1) Antoine Semenyo (Bournemouth to Manchester City) £65m

Always likely to the be the most hotly anticipated deal of the month since the world and his dog were aware of the winger’s £65million buy-out clause that had to be activated in the the first fortnight of the window. City were more decisive than Liverpool, Manchester United, Tottenham and probably a host of other clubs too.

2) Brennan Johnson (Tottenham to Crystal Palace) £35m

Palace wasted no time in signing Spurs’ Europa League matchwinner, agreeing to break their transfer record before the window even opened to see off Bournemouth when they were looking for a replacement for Semenyo. Johnson’s sale did not go down well with the Spurs squad.

3) Taty Castellanos (Lazio to West Ham United) £26m

There was at least some haste about the Hammers, who knew they had to act this month if they had a hope of staying in the Premier League, and among their priorities was another stab at signing a competent striker. Castellanos only scored twice in 12 appearances for Lazio this term but the Argentina striker is already off the mark for his new club, scoring an extra-time winner to see off QPR in the FA Cup to put on hold West Ham’s search for a new manager.

4) Matteo Guendouzi (Lazio to Fenerbahce) £24.3m

The former Arsenal midfielder signed his contract on Thursday then, on Saturday, scored on his debut to help Fenerbahce beat Galatasaray, which goes some way to repaying the record fee coughed up by the Turkish club. Guendouzi is still only 26, which surprised us…

5) Gerson (Zenit to Cruzeiro) £23.4m

Having flip-flopped between Brazil and Europe, the 28-year-old returns to his homeland where he becomes the Brazilian league’s most-expensive player. Zenit have done well to get their money back for a player who played only a dozen games and was six months into a five-year contract.

6)  Pablo (Gil Vicente to West Ham) £18.3m

West Ham could be liable for another £2.6million in add-ons for the 22-year-old  forward, who scored 10 goals in 13 appearances in the Portuguese top flight. Handily, Pablo and Nuno are both clients of Jorge Mendes.

MORE: Every Premier League deal completed in the 2026 January transfer window

7) Kenneth Taylor (Ajax to Lazio) £14.6m

The 23-year-old Ajax academy product moves to Lazio to replace Guendouzi after opting for the Serie A club over Porto and Galatasaray. Ajax could bank another £1.7million from potential add-ons, while Lazio have sold two talents for around £50million combined and replaced them for roughly half that amount.

8) Rodrigo De Paul (Atletico Madrid to Inter Miami) £13m

The midfielder joined Inter Miami in the summer, initially on a controversial loan deal seemingly arranged to sneak the 31-year-old in under the designated player limits. It was a mere formality that the arrangement was made permanent recently, with De Paul taking one of the DP spots opened up by the retirements of Sergio Busquets and Jordi Alba.

9) Luis Guilherme (West Ham to Sporting Lisbon) £12.1m

The Brazilian made almost no impact in 18 months at West Ham before being sold for around half the price the Hammers paid Palmeiras in 2024. But they could claw back more with £2.6million potentially due in add-ons plus a 15 per cent sell-on clause.

10) Petar Ratkov (RB Salzburg to Lazio) £11.3m

Lazio swooped to sign the 22-year-old as a replacement for Castellanos, though Maurizio Sarri was evidently not involved in the deal: “I don’t know this player. The other people who work at this club probably know him better than I do. But to be honest, I don’t know what to say about him. I don’t know him, and that’s normal, because I don’t have time to watch the Austrian league.”