The EastEnders star was sent home after receiving fewer votes to save than the Shannon twins, Romeo Dunn, Frankie Cocozza, Denise Welch, Nicola McLean and Michael Madsen.
Upon hearing the news from host Brian Dowling, Cassidy grinned and clapped her hands excitedly before moving forward to say her goodbyes.
She left the house to the "lovely response" that Dunn had predicted for her, enthusiastically waving as she made her way down the stairs.
Fellow nominee Kirk Norcross was eliminated earlier tonight.
Cassidy had been the bookmakers' early favourite to win this year's Celebrity Big Brother.
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