Credit-eating fees probed

The country’s competition watchdog says it is assessing complaints it has received about an ‘‘account administration fee’’ introduced by Vodafone in February that whittles away credits owed to former customers.

Separately, Spark said on Wednesday that it was attempting to refund more than $1 million to 135,000 former broadband and mobile customers. Spark admitted at the same time that it was being investigated by the Commerce Commission over billing errors which it said were behind a minority of the ‘‘credits’’. Asked whether the commission was investigating other companies over similar matters, a commission spokeswoman said it had ‘‘a number of investigations under way into conduct in the sector’’.

‘‘We will be in a position to talk about these publicly once the investigations are complete,’’ she said.

In February, Vodafone introduced a $5-a-month ‘‘account administration fee’’ for customers who left the company with their account in credit.

The charge applies to customers who have been inactive for six months and is ‘‘used to cover the costs of Vodafone holding on to credit balances for inactive accounts’’, according to a statement on Vodafone’s website.

Spokeswoman Elissa Downey said customers would pay the fee if they ‘‘stop using our service but do not close their account’’.

Before imposing the charge, Vodafone gave customers at least 30 days’ notice of the fee and did ‘‘inform them of the steps they need to take their credits back into their accounts’’, she said.

‘‘If the account reaches a $0.00 balance, you will no longer be charged the account administration fee,’’ Vodafone’s website states.