The Commerce Commission is reminding businesses that while charging a holiday surcharge is not illegal, failing to inform customers that a surcharge applies is.

Director of Fair Trading Deborah Battell said that with Anniversary Day holidays approaching in Wellington, Southland, Auckland and Nelson, the Commission was concerned to ensure that businesses were aware of their obligations under the Fair Trading Act and that consumers were aware of their rights.

"Under the Fair Trading Act, businesses must clearly identify all the costs or charges that the buyer of the goods or services will have to incur at the time an offer or representation is made," Ms Battell said.

"This means that customers must be made aware of any holiday surcharge that applies before they make a decision to purchase.

"If a customer isn't told a surcharge applies, then the business may be acting illegally by insisting they pay it."