Emails can end up in the spam folder for a variety of reasons, most of which are related to spam filters and email providers’ efforts to protect users from unwanted or potentially harmful content. Here are some common factors that can cause emails to be marked as spam:
- Content and Formatting: Spam filters analyze the content and formatting of emails. If an email contains certain keywords often associated with spam (e.g., “free,” “win,” “earn money fast”), excessive use of capital letters, excessive punctuation, or poor HTML coding, it might be flagged as spam.
- Sender Reputation: Email providers maintain a sender reputation score for each sending domain and IP address. If the sender’s reputation is poor due to a history of sending spam or engaging in suspicious behavior, their emails are more likely to be marked as spam.
- Authentication and SPF/DKIM/DMARC: Properly authenticated emails using protocols like SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting, and Conformance) are less likely to be flagged as spam. These authentication methods help verify that the email is coming from a legitimate source.
- User Engagement: Email providers take into account how users interact with emails. If users frequently mark emails from a particular sender as spam or if they don’t open or interact with emails from that sender, future emails from that sender might be filtered as spam.
- Unsubscribing and Opt-Out: If an email lacks a clear and functional unsubscribe option, or if the sender continues to send emails to recipients who have unsubscribed, this can trigger spam filters.
- IP Address Reputation: The IP address from which the email is sent plays a role in determining whether the email is flagged as spam. If the IP address is associated with known spammers or has a poor reputation, the email is more likely to be marked as spam.
- Volume and Frequency: Sending a large volume of emails in a short period or sending emails too frequently can trigger spam filters. This behavior is often associated with spammers.
- Attachments and Links: Emails with suspicious attachments or links to malicious websites are likely to be marked as spam. Similarly, if the linked website has a poor reputation, it can negatively impact email deliverability.
- Blacklists: If a sender’s domain or IP address is listed on email blacklists maintained by various organizations, their emails are more likely to be marked as spam.
- Content Similarity to Known Spam: Emails that closely resemble known spam messages in terms of content, structure, or formatting are more likely to be flagged.
To avoid having your legitimate emails marked as spam, it’s important to follow best practices for email marketing, maintain a positive sender reputation, use proper authentication methods, provide clear opt-out options, and avoid using spammy content and formatting. It’s also a good idea to periodically check email blacklists to ensure that your sending domain and IP address are not listed.