AIB has said that mortgage interest tax relief payments that were not made at the end of February will be paid in full 'as soon as possible'.
The bank says the 28th of February falling on a weekend was to blame for the problem, and that 1,600 accounts were affected.
It comes after it was reported this weekend that the error left thousands of families out of pocket, with some ending up overdrawn.
According to reports yesterday the blunder was costing families up to €375 each, and the State-owned bank was refusing to immediately rectify the mistake and instead insisting on repaying the money over the remainder of the year.
In a statement today, the bank says, "for mortgage payments scheduled for the 28 February 2015, tax relief at source payments were not immediately made as the 28 February fell over a weekend. This impacted an estimated 1,600 mortgage accounts.
"AIB confirms that the tax relief at source for that month will be paid in full in one payment on these accounts as soon as possible. AIB regrets any inconvenience caused. AIB is keeping the Central Bank of Ireland fully informed on the matter," the statement adds.