1. Sender Reputation
Your sender reputation is crucial. If you consistently send valuable, relevant content, your emails are more likely to land in inboxes. A poor reputation - often due to spam complaints, high bounce rates, or sending to invalid addresses—can lead to blocked or filtered emails.
2. Email Content & Formatting
Spam filters analyze your email's content to determine if it’s trustworthy or spam. Factors like excessive capitalization, misleading subject lines, too many images versus text, or trigger words (e.g., "free money," "urgent offer") can impact deliverability. Well-crafted, relevant emails with a balanced text-to-image ratio are more likely to reach inboxes.
3. Recipient Engagement
Email providers track how recipients interact with your emails. High open and click-through rates indicate valuable content, while low engagement (e.g., ignored emails or frequent unsubscribes) may result in future emails being filtered as spam. Encourage engagement by sending personalized, relevant content and avoiding email fatigue.
4. List Quality & Hygiene
A clean, up-to-date email list improves deliverability. Sending emails to outdated, inactive, or purchased lists increases bounce rates and spam complaints. Use double opt-in methods and regularly remove invalid or unengaged contacts to maintain a healthy list.
5. Email Authentication (SPF, DKIM, DMARC)
Authentication protocols help verify that your emails are legitimate:
SPF (Sender Policy Framework): Prevents unauthorized sources from sending emails on your domain’s behalf.
DKIM (DomainKeys Identified Mail): Adds a digital signature to prove your email is authentic.
DMARC (Domain-based Message Authentication, Reporting & Conformance): Enforces SPF and DKIM policies, protecting against spoofing and phishing.
Properly configuring these records strengthens your email’s credibility and prevents rejection by mail servers.
Test your email for free test.smtp.ai
6. IP and Domain Reputation
Email providers monitor the reputation of your sending IP and domain. If you're on a shared IP, the behavior of other senders can affect your deliverability. A dedicated IP allows better control but requires warming up gradually. Consistently sending high-quality emails improves domain reputation over time.
7. Sending Practices (Volume & Frequency)
Sudden spikes in email volume or inconsistent sending patterns can trigger spam filters. To avoid this:
Warm up new domains and IPs by gradually increasing sending volume.
Maintain a consistent sending schedule.
Segment lists to ensure targeted, relevant emails.
8. Blacklists & Spam Traps
If your domain or IP lands on an email blacklist (due to spam complaints, poor sending habits, or hitting spam traps), your deliverability will suffer. Regularly monitor blacklists and use email validation tools to prevent sending to risky addresses.
9. Compliance & User Preferences
Regulatory compliance (e.g., GDPR, CAN-SPAM, CCPA) and respecting user preferences also affect deliverability. Always provide a clear unsubscribe option, honor opt-outs promptly, and avoid misleading email practices to stay compliant and maintain trust.
Our skilled RepHero monitor team is ready to helpBuilding and keeping a good email sending reputation all comes down to using opt in data and sending content people want see and click from the inbox. In short "play by the rules"
Get live reportsIf any changes happens on your sending domain or IP, good or bad, you will get an update by email, messenger client showing the status so you are not in the dark and able to take quick action.
Email certificationsmySMTP deliverability assistants will guide you through all DNS configurations for RDNS, DKIM, SPF, DMARC and more.
Feedback LoopsOur feedback loops are your direct link to understanding how recipients engage with your emails. They provide invaluable insights by reporting spam complaints, helping you enhance sender reputation and fine-tune your email marketing strategy.