Customers who have signed up for Irish Broadband's entry-level wireless internet service may be paying up to €4.50 per month more than they could be.

The firm, which is owned by National Toll Roads and Kilsaran Concrete, became embroiled in a dispute this week with rival firms and the regulator over its adherence to its broadband licence.

It is understood the Commission for Communications Regulation (ComReg) has told the firm to provide details of its €25.49 per month service, which the firm had pledged to introduce in the initial licence competition.

Up until yesterday, Irish Broadband had only been actively marketing a €29.99 per month entry-level broadband service for customers. This service offers customers broadband at a speed of 512 kilobytes per second and is paid through a bill every month.

However, in a competition organised by ComReg to award licences to applicant firms with the best offerings, Irish Broadband pledged to introduce a cheaper service for consumers.

The licence obligations, which have been obtained by The Irish Times, show Irish Broadband pledged to introduce a 512 kilobyte per second service for €21.07 excluding VAT. When VAT is added, this service should cost €25.49 per month.

In the products section of Irish Broadband's website, the firm has only actively marketed its €29.99 broadband service - called Ripwave - to people. Up until Thursday, there was no mention of the cheaper Ripwave product on this part of the site.

And the sales department did not mention the cheap service to The Irish Times yesterday in a call to a sales person until it was brought to their attention.

An Irish Broadband spokeswoman said yesterday that customers hadn't to date signed up for the cheaper product. "It is not a product that we push but it does comply with the regulations," said the spokeswoman, who added that it would be looking at its pricing policy again shortly.

But following the meeting with ComReg and other wireless operators this week, Irish Broadband posted a new section on its website (labelled ComReg compliance), in which it lists the €21.07-per-month product as available to people who pay a year in advance. The compliance section of the website also lists the cheapest business service for a fee of €51.82 excluding VAT.

It is understood that wireless operators that took part in the licence competition organised by ComReg have raised the pricing issue with the regulator. At least one operator that lost out to Irish Broadband in the competition has alleged that it is not complying with licence obligations.

A ComReg spokesman said yesterday that Irish Broadband remained in compliance with the terms of its licence obligations.

A full list of licence obligations for wireless operators is published below. All the broadband products should be available to consumers who ask for them at the prices listed plus a 21 per cent charge to account for VAT.

Last night, ComReg said it would publish the obligations.