Over €3 million in refunds will be paid to affected customers.
Over 100,000 people are due to be refunded about €33 from Virgin Media.
In a ComReg investigation, the company was found to be continuing to charge its customers after they had cancelled their contracts.
Over 3 million euro in refunds will be paid to the affected customers by March 31st.
In a statememt, Virgin Media said it takes regulatory compliance extremely seriously.
"It is our position that we are in full compliance with all our regulatory obligations," the company added.
It has set up a dedicated helpline for customers to call in respect of the refund process and affected customers may contact Virgin Media via its helpline on 1800 941 770.
Information will also be available on its website for customers affected by the issue, it added.
