Reasons for spam filters and deliverability of newsletters

Many companies and organizations rely on newsletters to reach their target groups. However, these emails often end up in the spam folder - for a variety of reasons. In this article, you will find out what you should pay attention to so that your newsletters arrive reliably in your inbox.

Content and technical requirements

It is often trivial things that lead to a newsletter being classified as spam. The content plays a major role: mail services analyze texts and links and decide whether it is potential spam. But the technology behind it is also crucial.

Important technical measures include, for example, DNS adjustments with an SPF record or DKIM. These settings help to improve the deliverability of your emails. The reputation of your domain is just as important - it should have a good reputation so that your messages are not blocked.

Email check: How to check your deliverability

To make sure that all technical requirements are met, we recommend using an email checker. There are special websites where you can create a temporary email address. Send your newsletter to this address and have the site check the most important points:

- Technical framework conditions such as SPF record and DKIM
- Problematic content or hidden characters that may occur when copying from other programs
- Links that could trigger spam filters
- References to social media links that increase the spam score

A service that we use quite frequently: https://www.mail-tester.com/
At the end, this tool gives you an assessment of how likely it is that your newsletter will be caught by a spam filter. If the indicator lights up orange or red, you should revise the content again. If it is green, there is a very good chance that your email will end up in the inbox.

Conclusion

You can significantly improve the deliverability of your newsletter with a few targeted measures. Make sure your content is clean, optimize the technical settings and check your emails with an email check before sending. This will ensure you reach your recipients reliably - and your newsletter won't end up in spam.

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Michael Salzer
WordPress professional, Apple fan and irregular jogger.

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