How to avoid marked as spam?

Mail servers have spam filters that evaluate incoming messages for spam characteristics.

Weronika Kapias avatar
Written by Weronika Kapias
Updated over a week ago

If a message meets spam criteria, it may be automatically assigned to the spam folder.

A message can be marked as spam in two ways - by the recipient's server or by the recipient of the message itself.

To avoid messages being marked as spam, it's a good idea to follow a few key rules and practices:

Gather consent to subscribe

Make sure recipients have given informed consent to receive your messages. Do not send emails to people who do not voluntarily subscribe to your mailing list.

Segment your subscriber list

Tailor content to your audience's interests and preferences, avoiding sending un-targeted messages in bulk.

Ask questions and collect feedback

Encourage recipients to provide feedback on the content of your messages, allowing you to better adapt your email marketing strategy.

Check the security of your mailings

Be sure to add authentication entries for your sending domain, and use other tools to confirm the authenticity of your domain.

Monitor campaign metrics

Regularly analyse campaign metrics such as open rate, click-through rate, and spam marking rates to better adapt your marketing strategy.

Allow easy unsubscribes

Include an unsubscribe link in every message, allowing easy unsubscribes, which can reduce the propensity for your emails to be flagged as spam.

Confirm regulatory compliance

Verify that your emails are compliant with applicable laws, such as RODO (GDPR), regarding privacy and the processing of personal data.

Provide value and avoid provocative or misleading words

Ensure that the content of your messages is of value to your audience, while avoiding the overuse of keywords characteristic of spam. Avoid being seen as desperate, intrusive or using quirky phrases, which can damage the reputation of your marketing emails.

Consult your email service provider

If you are experiencing difficulties, contact your email service provider, obtaining feedback on why your emails are being marked as spam and possibly requesting that your IP address be whitelisted.

Maintain consistency and transparency

Ensure that the email header clearly shows who the sender is, ensuring transparency and trust with recipients.

The 60:40 rule

Optimise the image-to-text ratio in the content of emails. Spam filters react negatively to excessive images, which can result in the message being placed in the spam folder. In addition, many email programmes block the display of images by default, which can make it difficult for recipients to access content. To minimise the risk, keep the image-to-text ratio at around 60:40 in favour of text.

Following these rules will help maintain a positive sender image and minimize the risk that your messages will be marked as spam by recipients.

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