The monthly service fee tops the list of most-hated bank fees in 2015, with almost one-third of U.S. consumers (31 per cent) choosing it as their most hated, according to a recent study from Austin, Tex-based Kasasa.

After monthly service fees, ATM fees (26 percent) are consumers’ second most-hated charge, according to the second annual banking study, which was conducted online by Harris Poll in January 2015 and surveyed more than 1,000 U.S. adults (ages 18 and up) on behalf of more than 280 community financial institutions offering the Kasasa brand of checking accounts.

While 92 per cent of consumers claim to be aware of the fee structure at their bank, one in four still feel scammed by bank fees. Customers of the big national banks and millennials are more likely than their counterparts to feel this way. Big bank customers (36 per cent) are twice as likely to feel scammed by bank fees compared to community bank and credit union customers (14 per cent), and 30 per cent of millennials feel scammed compared to just 16 per cent of U.S. adults ages 55 and up.

According to the study, big bank customers are also three times as likely to consider more or higher fees to be a disadvantage of their bank (23 per cent) over community bank and credit union customers (7 per cent).

Half of community bank and credit union customers (49 per cent) say their checking account is free no matter what, compared to just 14 per cent of big bank customers.

The study found that two out of three U.S. adults (66 per cent) would rather bank at a community bank or credit union than one of the big national banks, if everything were equal.