During the back of 2023-24, the versatile defender proved to be one of the Blues' key players having missed the first half of the campaign through injury.
In the 10 games in which Chalobah started in the Premier League under Mauricio Pochettino, Chelsea accumulated 24 points, a pivotal surge that secured European football for this season.
However, once the academy graduate was omitted from the 28-player squad for the pre-season tour of the United States, it became clear that he was not part of the Italian's plans.
The 25-year-old has been available to leave from then onwards, yet Chalobah has never been in any rush to depart his boyhood club for a team that he did not feel inclined to join.
Palace strike late deal
As such, his future was up in the air throughout deadline day, the possibility remaining that he could be kept at Stamford Bridge until at least January.
Instead, Palace were able to strike a deal with their Chelsea counterparts for Chalobah to make the switch to Selhurst Park for the rest of the season.
Although the transfer was not confirmed until Saturday morning, a registration request was put forward before Friday's 11pm deadline.
What has Chalobah had to say?
Speaking to the club's official website, Chalobah said: "I'm delighted to join an ambitious club like Crystal Palace.
"I know some of the boys in the squad well and I'm looking forward to playing alongside them in front of the amazing support at Selhurst Park."
Despite successfully fending off interest from Newcastle United for Marc Guehi, Palace have needed to react to a double blow in recent weeks.
Not only has Joachim Andersen linked up with Fulham, Chadi Riad sustained a knee injury during the EFL Cup win over Norwich City on Tuesday.
Wolfsburg defender Maxence Lacroix was also signed by the Eagles on deadline day to bolster Oliver Glasner's options.