Retailer or chain leaflets are printed advertising materials distributed to mailboxes without a specific address. They highlight promotional offers on upcoming products and have long been a crucial element in attracting customers to stores. In 2018, retailers such as Lidl claimed to distribute 12 million leaflets each week, while Monoprix sent out 30 million. The distribution of these leaflets can be assessed through ad hoc studies or tracked and analyzed by specialized organizations. For more information and figures on this subject, various sources such as industry reports can be consulted.

A concrete example is provided by the leaflets of the Leclerc chain. A study conducted by OpinionWay for Bonial in 2015 measured the frequency with which these advertising materials were received. There are also monthly reports that analyze leaflet activity in the food retail sector.