Consumers should be wary and resist pressure to purchase vouchers from telemarketers that appear to make their holiday dollars go further, the Commerce Commission said today.

The commission said it was aware some consumers had been phoned by businesses claiming to be selling vouchers or schemes for discounted accommodation in New Zealand and Australia.

Some consumers found the vouchers could not be used in all the places promised, while others were concerned they had signed up for a membership that would be automatically renewed, the commission said.

"These types of schemes have been marketed in New Zealand for some years now. In our experience some are legitimate and others are not," Wellington commission enforcement manager Greg Allan said.

It was important consumers took the time to check their vouchers delivered what was promised, before they handed over their credit card details.

"Once you have purchased vouchers, it can be very difficult to get your money back if they don't deliver the benefits you expected," Allan said.

Any company selling vouchers that are not redeemable for the services that they claim risks breaching the Fair Trading Act.

In 2007 the commission took court action against a group of Australian companies operating in New Zealand under the name Discount Premium Holidays Ltd, their director, and associated companies, who were marketing a voucher programme in New Zealand.

The company was prohibited from making false and/or misleading representations about the cost and validity of their holiday voucher programme.