The damage caused by phishing ranges from denial of access to email to substantial financial loss. It is estimated that between May 2004 and May 2005, approximately 1.2 million computer users in the United States suffered losses caused by phishing, totaling approximately US$929 million. United States businesses lose an estimated US$2 billion per year as their clients become victims. In 2007, phishing attacks escalated. 3.6 million adults lost US$3.2 billion in the 12 months ending in August 2007. Microsoft claims these estimates are grossly exaggerated and puts the annual phishing loss in the US at US$60 million. In the United Kingdom losses from web banking fraud—mostly from phishing—almost doubled to GB£23.2m in 2005, from GB£12.2m in 2004, while 1 in 20 computer users claimed to have lost out to phishing in 2005.
According to 3rd Microsoft Computing Safer Index Report released in February 2014, the annual worldwide impact of phishing could be as high as $5 billion.
The stance adopted by the UK banking body APACS is that “customers must also take sensible precautions … so that they are not vulnerable to the criminal.” Similarly, when the first spate of phishing attacks hit the Irish Republic’s banking sector in September 2006, the Bank of Ireland initially refused to cover losses suffered by its customers (and it still insists that its policy is not to do so), although losses to the tune of €11,300 were made good.