A filling unit for contact or contactless filling an article is disclosed. The filling unit includes a tank comprising: a first valve, which may allow or prevent the fluidic connection between a first region of the tank and the article; a first fluidic line which extends from the tank to the article in case of contact filling; a second valve, which may allow or prevent the flow along the first fluidic line; and a control unit configured to set the first valve in a first closed configuration and the second valve in a second open configuration in case of contact filling. The filling unit further includes a second fluidic line distinct from the first fluidic line and extends from the inner volume of the article to a discharge area distinct from the tank; and a third valve, which may allow or prevent the flow along the second fluidic line.