Deliverability update: This is how your emails are well received
The most perfect email campaign can't achieve its marketing goals if it isn't delivered reliably to recipients. Good deliverability is therefore not a side issue for experts — but the indispensable basis for successful email marketing. Email marketers should therefore know the key deliverability levers and use them for themselves.
While selecting the appropriate sending service deliverability should be an important decision criterion for companies. Ask platform providers what measures they are taking to optimize deliverability and whether a dedicated team of experts can help you with advice and assistance!
Even with the Design and production of every email campaign Email marketers should always keep an eye on their sender reputation. This is the only way they can guarantee consistently good deliverability and correspondingly high opening and click rates.
We have put together an overview of the five most important parameters for good deliverability for you.

1. User Response: Welcome to the age of user engagement metrics!
Large email service providers are increasingly relying on the collective response of their users when it comes to determining whether a sender is sending desired or unsolicited emails. In this context, “big data” means that it is entirely possible today to collect and systematically evaluate a wide range of user response data: Whose emails are stored in the recipients' inbox for a longer period of time, opened or answered often? Whose emails regularly end up unopened in the trash or are even marked as unwanted spam? Which sender is frequently added to their recipients' address books? User engagement is now a key deliverability factor. For senders, this means that relevant, high-quality content and the most accurate targeting possible are becoming more important than ever.
2. Campaigns: Ensure safe code and high-quality content!
The design of emails continues to play a role in their deliverability that should not be underestimated. HTML emails should generally be neatly coded and contain no scripts or embedded content — even attachments that could be classified as potentially harmful by email providers should be avoided. Make sure the quantity ratio between text and image is healthy, as well as correct links. A text version should always be available. A high level of personalization is recommended for the content. By including a personal greeting and other elements, none of your marketing emails are exactly the same. This is how your mailings stand out from spam mailings, which send emails with identical content en masse. Legally, the content should of course also be correct: Advertising content must be clearly recognizable as such. A complete legal notice, a reference to data protection regulations and an unsubscribe link are mandatory components of every marketing email.
3. Dispatch lists: list management, list management
Hardly anything can damage your sender reputation as quickly and as thoroughly as poorly maintained mailing lists. This is because these lead to high bounce rates, critical spam complaints and poor response figures — and can also contain dangerous spam traps, which ensure that you are blacklisted as the sender. Your address database should therefore be maintained regularly and thoroughly.
Read more: 5 practical tips for good list management
4. Technical configuration of the sending system
In order for your marketing emails to be delivered reliably to the recipients' inboxes, everything must also be right with the infrastructure you use to send your emails. For mass senders, email providers attach particular importance to ensuring that email delivery is as resource-efficient as possible in accordance with the applicable standards and for the receiving mail server and that sending mail servers are protected against attacks from outside. The sender of an email should also be identifiable as reliably as possible; in case of problems, the complaint process should run smoothly. Even if, as an email marketer, you leave the technical set-up of the infrastructure to others, value good technical configuration — and check for yourself what the header area of your email actually looks like.
Read more about this topic:
5. Contractual agreements/whitelisting
Does the operator of your email marketing platform maintain special contractual agreements with individual Internet service providers (ISPs)? If so, it's an added bonus to the deliverability of your marketing emails. Large platform providers sometimes have very individual agreements with specific ISPs. In addition, senders can also participate in whitelisting projects organized by associations, such as the Certified Senders Alliance (CSA). Anyone who sends their marketing emails via a CSA-certified platform has easier access to the mailboxes of participating ISPs — including heavyweights such as GMX, Yahoo and Vodafone. Inclusion in the CSA involves a complex certification process and strict acceptance criteria for shipping service providers: Only after the sender has been able to provide sufficient evidence that the marketing emails sent by their customers (will) meet the technical and legal requirements will they be treated preferentially by the participating ISPs.
But be careful: CSA whitelisting does not automatically solve all problems.
Read which points you should definitely consider.
Large email service providers now use highly complex processes to distinguish relevant, desired emails from unwanted spam as reliably as possible. The filter methods differ from provider to provider. Email providers are constantly developing their systems in the race against spammers. In order to prevent misuse, they often do not fully disclose their evaluation procedures. For mass senders of commercial emails, however, many major providers provide guidelines that can achieve high deliverability rates by following them. Here are examples of policies and best practices from major email service providers:
- United Internet: GMX, Web.de
- Google: gmail
- Microsoft: Outlook
- Yahoo: Yahoo Mail
Also read our Publicare email study: Germany's marketing emails are delivered to these providers