Why do my emails end up in spam?

Do your emails often end up in your recipients’ junk mail? Email deliverability is not an exact science, as it depends on many factors. It is important to note that the criteria for spam categorization vary depending on Internet Service Providers (ISPs) and email clients. In this article, we will explain how to know whether your emails are classified as spam, the most frequent reasons behind this classification, and how you can reduce the risk of ending up in spam.

What is spam?

Spam refers to unsolicited and unwanted emails sent in bulk. These messages are often promotional or advertising in nature, and they are sent on a large scale without the consent of the recipients. Email providers implement filters to identify these emails and filter them before delivery or automatically direct them to the junk mail folder, in order to protect their users against spam.

How can I tell whether my emails reach the inbox or not?

Check your open and click rates

Abnormally low open and click rates may be a sign that your emails are being filtered as spam or are being filtered upstream by the servers.

Monitor bounce backs and error messages

Non-delivery or rejection messages may indicate that your emails are being filtered even before reaching your recipients’ inboxes.

Perform sending tests

Send your emails to test addresses to check whether they arrive in the inbox, in the spam folder, or do not arrive at all (and are therefore filtered upstream).

The most frequent causes

Content of the message

Content including words frequently associated with spam (also known as spamwords), suspicious links, or poorly formatted content may trigger alerts from spam filters.

Unqualified mailing list

The use of non-opt-in email lists or sending to recipients who have not consented to receive your emails may result in being classified as spam.

Sender reputation

If your IP address or domain is associated with past spam sending, this may affect the deliverability of your emails

Lack of engagement

 ISPs often consider emails without interaction (opening, click, reply) as suspicious.

Technical issues 

Configuration errors of the sending server or domain validation issues may also impact the classification of your emails.

Measures to implement to avoid the spam folder

Opt-in and subscription management

Obtain the explicit consent of recipients and allow them to manage their subscriptions.

Content quality

Write relevant, well-structured emails that are free of suspicious terms.

Avoid suspicious attachments

Avoid sending dubious attachments or executable files.

Authentication SPF/DKIM/DMARC

Implement these protocols to strengthen the authenticity of your emails.

Reputation monitoring

Use monitoring tools to track the reputation of your IP address and your domain.

Avoid questionable practices

Do not hide the unsubscribe option, do not purchase email lists and, in general, do not use techniques associated with spamming.

Segmentation of mailings

Send targeted emails based on the recipients' interests.

By following these recommendations, you will increase your chances of delivering your emails directly to your recipients' inboxes, rather than having them filtered at the beginning of the delivery chain or ending up in the spam folder.