The Certified Senders Alliance (CSA) has pursued the objective of strengthening quality and security in commercial bulk email sending and improving the delivery of emails since 2004. As a project of eco – Association of the Internet Industry in cooperation with the German Dialogue Marketing Association (DDV), the CSA acts as a link between senders and mailbox and spam filter providers.

In 2025, the CSA focused on further expanding its role as a globally established player in the email ecosystem: new partnerships, intensified data exchange, and active participation in the national debate on email security.

Certification Programme

At the core of the CSA is the IP certification programme with its clearly defined quality and security standards for email sending. Certified senders receive access to real delivery data from the CSA partner network via the CSA monitoring tool “Certification Monitor”, provided on the basis of IP and domain.

By the end of 2025, the programme comprised 96 certified senders with 115,552 IPs and 1,156,879 domains under monitoring – supported by a network of over 45 national and international partners in the email ecosystem.

Further Development of the Monitoring Tool

Continuous monitoring has become an indispensable prerequisite for secure email sending and reliable delivery. The CSA Certification Monitor has therefore been specifically enhanced and strengthens its function as an early warning system for the targeted identification and resolution of reputation and authentication issues. Additional new DKIM metrics enable targeted error analysis, while a rolling seven-day view further supports the tracking of trends in key metrics. Personalised, user-specific alerts for DKIM errors as well as extended DNS and rDNS reporting facilitate the identification of technical configuration issues.

Network Expansion 

Through partnerships with Orange France and mail.de, the application of the CSA Certified IP list has been further expanded. This collaboration creates the basis for future exchange of additional reputation and complaint data to expand the CSA data base and the reach of certification, including internationally.

CSA Supporters in the Email Ecosystem

In 2025, the CSA received active support from various players who are likewise continuously committed to improving the email ecosystem.

With the shared objective of establishing industry-wide quality and security standards in email sending, structured exchange and continuous collaboration were carried out by the CSA with the following infrastructure, domain, security providers and technology partners: Dmarc Advisor, dmarcian, halon, Spamhaus.

Engagement in the Email Security Year 2025

As part of the Email Security Year 2025 initiated by the German Federal Office for Information Security (BSI), the eco Association and Bitkom, the CSA actively contributed to expert exchange by bringing in its practical experience in workshops and discussions on challenges and responsibilities for secure email sending. The CSA certification programme also promotes the active application of established security standards in day-to-day sending practices.