10 euro notes are to be added to ATM machines as part of a trial period scheduled for later this year.
The move is in response to demands for smaller denomination notes from those on lower incomes or social welfare.
The Consumer Association says the change is likely to increase ATM usage and corresponding bank charges.
CEO is Dermot Jewell.
"The banks will not lose out. At a time when all bank charges are returned - except to those of extreme wealth - we're finding a scenario where if you do want to take out that 10 euro through your ATM you will incur a bank charge" he said.
"It's one step forward, two steps back for consumers already struggling with money management" he added.