An investigation is underway after unsolicited messages were sent to some mobile phone users encouraging them to sign up for a subscription based text service.
It is illegal for companies to send texts without permission and the Regulator of Premium Rate Telecommunications Services says it is investigating the matter.
Details of the probe emerged as RegTel launched a new information campaign to increase awareness on how to opt out of subscription text services.
The regulator estimates that 75% of all calls to its helpline are from people trying to get out of these services.
The texts can cost up to €2 for every message received and over 80 million were sent in the last year.
Regulator Pat Breen says any customers wishing to cancel their subscriptions should text the word STOP to the service provider.
They will not be charged premium rates to do this and the companies are obliged to end the service at that time.
