Advertisements can be divided to binding and non-binding. This division has a meaning especially when the advertisement includes a mistake. A binding advertisement constitutes a binding offer for the seller and the trader cannot change e.g. the price of a product in the advertisement. The terms of the advertisement are binding for the seller and the seller has to sell the product on the price and on the other terms published in the advertisement if the client so wishes. The binding nature of an advertisement can be resolved only case by case, which can be on an individual case rather difficult. In case the purpose of an advertisement is to generally attract customers it normally is regarded as non-binding. For example, an advertisement published in a newspaper, on television or on the radio can be considered as a non-binding advertisement.
Consumers have the right to expect that the price and other information in the advertisement is correct on the site in the shop, in online shops and in address-based and other direct marketing, such as door-to-door and postal sales. In this case, the advertisement is binding. Exceptionally, the price is not binding on the seller if the consumer should understand that the price is considered to be abnormally low compared to the general price level.If the price information is, according to the seller, different from the price at which the order was placed, the seller must be able to provide reliable evidence of this.