This prohibition is based on the idea that consumers expect a "free" claim to be exactly that, meaning they receive something for nothing: no money or other consideration has to be given in exchange.
This is largely reflected in Annex I, n.20 which provides that an offer can be described as free only if consumers pay no more than:
a) the minimum, unavoidable cost of responding to the promotion (e.g. the current public postage rates , the cost of telephoning up to and including the national rate or the minimum, unavoidable cost of sending a text message);
b) the true cost of freight or delivery;
c) the cost, including incidental expenses, of any travel involved if consumers collect the offer.
As a consequence, traders should not charge for packaging, handling or administration.
It also follows that a legitimate promotion of free claims requires full price transparency from traders: traders should make clear in all material featuring "free" offers what is the consumer's liability for costs, if any.
An example of a prohibited practice would be where a consumer is offered a "free" product or a gift but then he or she needs to call a premium number to get it.
An example of a straightforward, legitimate free claim is when a trader hands out a free product sample to passers-by in a shopping centre.