A man walks past ATM machines at branch of the NatWest bank in Manchester, Britain September 21, 2017.
The bank's shares fell as much as 18% in early trading before closing down 12% - their largest daily drop since the Brexit vote in June, 2016.
Farage said in a statement on Friday that he viewed the report as a "whitewash" and its findings "laughable".
She added that the review showed she did not leak detailed financial information and had been unaware of "deeply unpleasant and unfair" internal staff comments made about Farage.
A NatWest document unearthed by Farage in July found that an internal committee had deemed his views did not align with the bank's own.
Persons:
Phil Noble, Nigel Farage, Coutts, Farage, Alison Rose, Travers Smith, Howard Davies, Rose, Mr Farage, Davies, Paul Thwaite, Rick Haythornthwaite, Iain Withers, Lawrence White, Samuel Indyk, Jason Neely, Sharon Singleton, Kirsten Donovan
Organizations:
NatWest, REUTERS, Financial Conduct Authority, Barclays, Rival, Lloyds, Thomson
Locations:
Manchester, Britain