A new survey by the financial regulator, IFSRA, has found wide discrepancies in the charges imposed on customers by different banks.
It shows that charges for a sample customer with a normal pattern of transactions can vary from nothing up to €112 a year.
The survey is the first study since the introduction of new switching codes that make it easier for customers to move from one bank to another.
It takes the example of a woman with an average balance of €50 at the end of each month.
The charges vary from each bank and also differ based on the type of account she uses.
Ulster Bank's U First Account is the most expensive, costing €112 per annum.
Both Permanent TSB's current account and National Irish Bank's Freebank have zero charges.
IFSRA recommends that customers should shop around for a bank. It says they should not only examine fees but also look at the levels of service like the availability of Internet and telephone banking which can cut costs.