uses cookies to analyze how the website is used, and to improve the user experience. Read more about cookies

This article is part of ‘Guidelines on the protection of the online consumer’. View full guideline

Rules regarding the ranking of search results

When searching or comparing products online, consumers must be able to have confidence in the results. If you change the ranking of search results, consumers will need to know on the basis of what factors you do so, because you cannot mislead consumers. If information about the ranking is missing or unclear, it is considered a misleading practice.

Are consumers on your website able to search for products or able to compare products from different companies or consumers? If so, you might present the search results or comparison results in a certain order. That order is called ‘ranking’. Your ranking may consist of ‘natural’ or ‘organic’ search results. These are search results that have not been paid for and that are on the basis of relevance to the consumer. Consumers expect these ‘natural’ results when performing a search on your website. You may also include products in your ranking or place certain products higher or more prominently in your ranking because a business paid you to do so (‘paid inclusion’ and ‘paid ranking’).

The ranking can greatly affect the decisions of consumers. Consumers often click on one of the first search results without paying any attention to the quality or relevance of that result. Also, they seldom change the ranking of the results. If you use paid inclusion or paid ranking, consumers might make different choices than they would have made with rankings that are not influenced (or only partially so) by paid inclusion or paid ranking.

That is why you need to explain clearly how you sort search results and comparison results, and whether they include any paid offers, so that consumers know what they are clicking on and that they are not being misled. The information that you give must be transparent. In that context, your language and the way you present information are important, for example the location and design of the information.

What is required and what is not allowed?

  • Present paid results in a significantly different manner than the ‘natural’ search results. In that context, think of colors, shapes, fonts, texts, images, sizes, and other layout choices. In addition, state clearly that businesses paid to be the top search result or to get a special spot in the search results. You can do so by using a label with a text that clearly explains that someone paid for this spot, for example ‘advertisement’ or ‘paid position’.

  • Do you offer consumers the option of searching for products from different businesses or private sellers? If so, inform consumers clearly about how that order is determined. Explain what the most important factors (‘parameters’) are on the basis of which the ranking of the search results or comparison results is made. In addition, inform consumers about how the different factors relate to each other, for example which ones are more important. Make sure that this information can be accessed directly and easily on the page where the search results and comparison results are presented, for example by placing a link next to the offers, which leads directly to the information page. That information must also be included in the general terms and conditions.

  • Present search results in an order that corresponds with the parameters that you communicated to the consumer.

  • Has a consumer entered a search query using a certain sorting selection or filters? If so, present your search results on the basis of the sorting selection and filters that were used.

  • Do you label certain search results, for example with labels like ‘Best buy’ or ‘Sustainable choice’? Make sure that such labels are true. Inform consumers on what basis such products have been labelled as ‘Best buy’ or ‘Sustainable choice’. For more information on sustainability claims, see the guidelines regarding sustainability claims.

  • Do not offer any paid search results without making clear what they are. This means that it needs to be clear to consumers if someone paid to give an ad a higher or more prominent position in the search results.

  • Do not leave out any search results that are relevant to the consumer’s search. In addition, do not place search results that are relevant to the consumer further down the list.

  • Did the consumer use sorting selections and filters? Respect those sorting selections and filters. Do not present any search results that do not correspond with the sorting selections and filters.

  • Do not hide any paid results in the natural search results.

  • Do not abuse A/B-tests by using them to decide how to inform consumers in a way that has the least effect on conversion. This harms consumers, because the goal of providing information is making sure that consumers actually see and understand the information, so that they are able to make a well-informed decision about whether or not to purchase a product.

  • Do not use misleading names for sorting selection options for search results, for example by using ‘sort by relevance’ or ‘sort by popularity’ while you actually sort by, for example, the payments for the paid results.


  • Test whether consumers immediately recognize the difference between natural and paid results.

  • Test what label for paid results or paid ranking is the clearest and easiest-to-understand for consumers.

  • Are certain products temporarily not available? If so, you may let consumers decide whether or not they want to see those results. In this way, consumers can decide, for example, to wait until the inventory has been restocked. Have the products been discontinued? In that case, leaving those out of the search results will be clearer.

  • You can ask consumers in advance if they want to see general or personalized search results. In that way, you offer consumers a neutral and free choice. Please note: if you offer personalized search results, you also have to inform consumers on what basis you personalize such search results. For more rules and tips, see also ‘Rules on personalized online offers’.


Example: Information about paid ranking

A company runs a real estate website. On this website, real estate listings of a realtor association are placed higher in the search results than listings that are not offered through that association’s realtors. The company receives a fee from the realtor association for doing so. This practice is not explained with the search results. It is therefore a misleading practice.

In this case, the company must clearly explain that the top search results only concern homes that are listed by certain realtors that have paid for it. The company can do so by adding a label that clarifies and explains that those higher rankings have been paid for.

Moreover, information regarding the most important parameters of the ranking of the real estate listings must be directly and easily accessible from the page on which the listings are presented.

Example: Sorting by relevance

A booking website for holiday accommodations offers the sorting option of ‘relevance’. However, in the results that were sorted using this option, ‘paid’ results are still placed higher. This practice is misleading. When sorting results by the sorting option of ‘relevance’, the company cannot take into account the factor of getting paid for boosting certain accommodations.

Relevant regulations

Explanation of regulations


ACM: Websites for booking holiday accommodations now inform consumers better about the ranking of their offers

ACM, together with the other European consumer authorities and the European Commission, confronted holiday platforms about, among other aspects, information regarding the ranking of the offers on their websites. The companies have changed their websites, and now inform clearly about: * The selection process behind the search results; * Certain search results are given a higher ranking because the providers offering them have paid for that higher ranking; * The total price of the accommodation includes all unavoidable costs; * The availability of rooms on certain dates: no more suggestions of artificial scarcity; * Deals must be genuine deals; * Prices, for example, a price cannot be presented as a discount if that is not the case; * If the host is a professional or a private person.

The information in the introduction of this chapter is based on the following studies and articles: