On a dramatic transfer deadline day, that also saw Jadon Sancho close in on a move to Stamford Bridge, the Gunners swooped to sign Sterling from their London rivals as they closed in on finally ending their attempts to sign a new attacker.
There is no obligation to buy option in the deal, finalised in the early hours of Saturday morning.
'You’re about to see the best of me,' Sterling said in a video posted by Arsenal on their X account.
Sterling has been told he has no future at Chelsea under Enzo Maresca and the club have been working to find him a new home.
Sterling has joined the Gunners on a season-long loan, but there isn't an obligation to buy
In a statement, Chelsea said: 'Chelsea winger Raheem Sterling has completed a season-long loan move to Arsenal.
'Raheem joined the Blues from Manchester City in the summer of 2022 and has scored 19 goals across 81 appearances.
'He will now spend the remainder of the campaign at the Emirates. Good luck, Raheem.'
Mail Sport reported on Thursday that Arsenal had been offered Sterling, along with Bayern Munich’s Kingsley Coman.
And Arsenal moved decisively to formalise their interest in Sterling on Friday afternoon before wrapping up the formalities of the deal.
Sterling’s £325,000-per-week wages was also viewed as the key stumbling block towards his departure during the window. But the two clubs have reached an agreement on how they will split his salary for the duration of the loan.
The 29-year-old will be reunited with Gunners boss Mikel Arteta, with whom he worked with successfully at Manchester City.
Meanwhile, Sancho will replace Sterling at Stamford Bridge as he closes in a loan move from Manchester United, where he was out of favour with head coach Erik ten Hag following their highly-documented fall-out.
The former Borussia Dortmund star is set to join the London side on loan with an obligation to buy. Sources are indicating the permanent purchase price is around £23million.