The striker, whose free transfer to Stamford Bridge from Anzhi Makhachkala was confirmed on Thursday, has been handed a one-year deal worth €117,000-a-week, some €293,000 less than in Russia.
Eto'o was the best paid player in world football at Anzhi, whose owner Suleyman Kerimov has moved to drastically reduce spending at the club, having previously sold Willian to the Blues for €38m on Sunday and a host of Russian talent to various domestic rivals.
Despite the mammoth loss in weekly earnings, Eto'o is still set to receive a substantial eight-figure severance package and signing on fee having completed the move to west London.
The former Barcelona star also receives €5.8m-a-year as a face of Puma, but has still seen his weekly pay-packet reduced by over 70 per cent.
Eto'o played under Chelsea boss Jose Mourinho during Inter's treble-winning 2009-10 campaign, before moving to the mega-rich Dagestan outfit in the North Caucasus.
He emerged as a target for the Blues boss after the club abandoned their pursuit of Manchester United striker Wayne Rooney, despite making two bids for the striker.
"I am very happy to be here but also anxious because I want to get playing as soon as possible," Eto'o told Chelsea's official website on Thursday.
"It wasn't a hard decision. I saw the qualities Chelsea have, and I was very happy with Jose Mourinho before, so when the opportunity came, I was very happy to take it."
Eto'o is Chelsea's sixth signing of the summer transfer window, joining Willian, Cristian Cuevas, Andre Schurrle, Mark Schwarzer and Marco van Ginkel at Stamford Bridge.
