Some 300 calls have been made to a phone line established by AIB in the wake of revelations that it has been overcharging for certain foreign currency transactions.
Most of the calls were requests for information from people who feared they may have been charged too much by the bank.
The bulk of the queries were from individuals and small businesses, according to an AIB spokeswoman.
There were also a number of inquiries at AIB branches around the State, although this was "more a trickle than a flood" she said.
"Most of the people are calling to look for information. They want to find out where they stand and if there is a possibility they were overcharged," she said.
The AIB helpline number is 1800 787 564 and will be open from 9a.m. to 5 p.m. today and tomorrow.
Banking watchdog the Irish Financial Services Regulatory Authority (IFSRA) received 360 calls to its consumer helpline by yesterday afternoon.
The majority of these were also requests for information.
IFSRA said it had taken the details of a number of callers who suspected they may have been overcharged by AIB.
The IFSRA hotline number is 1890 77 77 77. Messages can be left through the weekend.