Read the 'Amended defence and counterclaim of the fifth defendant - HSBCicon Bank PLC -

Par. 19 and following about the HSBC's Personal Banking terms and conditionsicon regulating the overdrafticon facilities... and the incorporated 'Fair Fees Policy'

I have been banking with them for the past 3 and a half years and everytime my account incurred a charge, they contravened the 'Fair Fees Policy' in which:

a) HSBC does not make a further charge if debited Arrangement fees (or interests) cause the account to go overdrawn or further overdrawn.

b) HSBC does not charge more than one Arrangement fee a day, no matter how many informally requested overdrafts are granted to the customer on that day.

c) HSBC operates further policies in relation to the charging of fees for the benefit of its customers, either as a matter of practice or discretion, including that i) no Arrangment fees are charged if the application of any interest or charges (including by way of example, the Return Fee) causes the account to go overdrawn or further overdrawn, and ii) the Arrangement fees payable for one month in respect of any one account will not exceed £150.00 in total.

Documents related to the test case can be read and downloaded here:
The Office of Fair Trading: Test case - documents