Retarus GmbH is an international information and communication technology company headquartered in Munich, Germany.
[4][5][6] In 1994, Retarus introduced fax- and eMail- consulting services as its core offering, allowing transmission of high volumes of faxes.
Its popularity has drawn advertisers like Amazon.de, Yellowmap, and Unertl Weißbier, who started using it for wake-up spots, banner ads, and email notifications.
[19] In 2022, Retarus partnered with DE-CIX, an operator of carrier- and data-center-neutral Internet Exchanges that allows users of DE-CIX to communicate through Retarus' cloud via a private direct connection that bypasses the public Internet, unlike VPN, Multiprotocol Label Switching or leased lines.
[23] In 2019, Retarus conducted another investigation, also reported by Frankfurter Allgemeine Zeitung, which found that fax usage was increasing among DAX-listed companies.