The reality star is said to have left the ITV2 series by mutual agreement after viewers complained of her being too dull, reports The Sun.
An ITV2 spokesman told Reveal: "I can confirm Georgina won't be in the new series of TOWIE."
Sources close to the socialite say that she wanted to leave the show in order to spend more time with boyfriend Tom Cleverley of Manchester United.
An insider said: "Georgina leaving was a mutual decision between her and producers.
"Her heart wasn't really in it and producers felt she didn't bring much to the show. She really wants to spend more time with Tom out of Essex."
However, a separate source claimed that Dorsett did not get on well with her co-stars and was looking for a way out.
"She was a bit of a damp squib and brought nothing to the show," the insider claimed. "She didn't really mix with any of the others and it didn't look like she wanted to be there."
Dorsett was apparently told back in April that she needed to "raise her game" in order to stay on the show.
The Only Way Is Essex returns for a sixth series on Sunday, July 22 on ITV2.
Photo gallery - 'The Only Way is Essex' - series six cast members:
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