How to avoid having your emails marked as spam

Table of Contents

Most emails are spam. Modern spam filter systems detect such spam emails and sort them out. The recipient never sees them. However, many desired emails are also mistakenly classified as spam, which is frustrating for both you as the sender and your recipients. Learn here how to ensure that your emails reach your subscribers' inboxes.

The Evaluation of Spam Emails

Spam emails are considered impersonal messages sent in bulk that are largely identical and are sent without prior consent from the recipient or contain irrelevant content for them.

Fundamentally, two types of spam are distinguished: Criminally motivated messages and unwanted marketing emails. The first group includes backscatter (automatically sent reply emails from forged sender addresses) and phishing emails (fraudulent emails sent to capture sensitive data like customer login, bank details, etc.). Unwanted marketing emails include Unsolicited Commercial Emails (UCE) and Unsolicited Bulk Emails (UBE).

Whether a message is considered a spam email is determined not only by the spam filter but also by the recipient. The evaluation of whether emails are considered spam significantly depends on the recipient's interest. The perceived annoying nature for the recipient is decisive. Of course, backscatter and phishing emails are inherently considered spam.

If a subscriber receives too many emails in succession and/or the content is irrelevant to them, emails can also be perceived as spam even if the recipient has already given permission to send them. Such emails are also known as bacn or greymails. Bacn refers to emails that are generally desired by the recipient but not at the time they are received. Greymails, on the other hand, are messages that are no longer relevant to the recipient despite having given permission. These emails usually pass through spam filters, but in both cases, you run the risk of having your subscribers unsubscribe from your email list.

How Spam Filters Work

The huge amount of unwanted emails makes the use of spam filters necessary. To ensure that your emails are not seen as spam, you must have a basic understanding of how spam filters work.

Spam filters are programs that try to evaluate the relevance of incoming messages and possibly identify them as spam. Today's spam filters are highly complex. The evaluation of messages is carried out based on defined evaluation parameters, which are embedded in a spam point system. Evaluation parameters include specific words or phrases in the sender address, subject line, and the email itself. In addition to such text modules, spam filters work with the reputation concept. A score is calculated based on certain criteria (sender, open rate, click rate, spam complaints, etc.) using various databases.

The specific configuration of this evaluation system is individually determined by each email provider. That means what is declared as spam by one provider may be classified as a