Bank of Ireland has come last, and Ulster Bank second last, in a banking study of British consumers by Which magazine.
According to the survey, Bank of Ireland had a consumer satisfaction rating of just 41% in Britain, while Ulster Bank's was 45%.
Bank of Ireland performed badly in relation to customer service, regular communication, clarity of statements and branch availability.
Ulster Bank's poor rating was blamed in part on the computer faults it suffered this year and last summer.
Responding to the survey, Bank of Ireland said its own independent research showed that 90% of customers are satisfied or very satisfied with the bank.
It said it would "continue to strive to improve on this figure" in the future.
