Thousands of Eircom customers will have to pay arrears of between €100 and €500 after an error in the company's billing system resulted in direct debits not being collected.

Around 30,000 customers did not have some or all of their monthly payments taken from their bank accounts for phone broadband and TV services since January.

They received their bills as usual however, which incorrectly stated the direct debits had been paid.

Eircom’s director of corporate affairs Paul Bradley said around 4 per cent of their customers had been impacted.

He said most of those affected would owe around €100, but this could rise to around €500 for some customers whose payments had not been collected for a longer period of time.

He said two-thirds of affected customers had already been contacted. Their next bill will reflect the full amount owed, including arrears, which will be paid by direct debit.

Chairman of the Consumers’ Association of Ireland Michael Kilcoyne has called on Eircom to write off the outstanding debts.

“The customer arranged for the payment to be made, they gave them the facility to do it, and Eircom botched it up,” he said.

“There are many people living hand to mouth now, who won’t be able to afford this. It is totally unacceptable that Eircom would demand this money from them.”

Mr Bradley said Eircom would arrange a payments plan for customers who are not in a position to pay the outstanding amount with their next bill.

“If they have any difficulties whatsoever in terms of paying, we are asking them please to contact us. We will work with them in order to put a payment plan in place,” he said.

The error is believed to be related to the implementation of the Single Euro Payments Area (Sepa) payment integration initiative.

Customers with queries about the error can call a dedicated phone line on 1800 303 432, Monday to Friday 9am-8pm.