Summary
The collective advice underscores numerous detrimental practices affecting email deliverability, categorized across list management, sending practices, and technical implementations. Buying lists, neglecting list hygiene, and failing to obtain explicit consent are consistently flagged as harmful. Incorrect technical setups, such as improper authentication, sudden volume spikes, and invalid formatting, also significantly impact deliverability. Furthermore, ignoring feedback loops, blocklists, and employing deceptive content tactics (misleading subject lines, hidden unsubscribe links) contribute to poor sender reputation and increased spam filtering. Ultimately, a proactive, ethical, and technically sound approach is essential for optimal email deliverability.
Key findings
- List Management: Purchasing email lists and neglecting list cleaning (removing bounces, unengaged users) directly harms deliverability due to spam complaints and invalid addresses.
- Consent: Sending unsolicited emails significantly increases the likelihood of being flagged as spam and damages sender reputation.
- Authentication & Tech: Failure to implement proper authentication (SPF, DKIM, DMARC), sending emails with incorrect formatting, and neglecting IP warm-up severely impact deliverability.
- Feedback Monitoring: Ignoring feedback loops from ISPs and failing to monitor blocklists results in poor sender reputation and reduced inbox placement.
- Deceptive Tactics: Misleading subject lines, hidden unsubscribe links, and using lookalike domains trigger spam filters and erode trust with recipients.
- Reliance on Quick Fixes: Switching ESPs upon IP blocking without addressing underlying issues is a temporary solution, not a long-term fix.
- Shared Responsibility Misconception: Assuming ESPs alone are responsible for deliverability can lead to neglect of crucial sender-side best practices.
Key considerations
- Prioritize Permission: Always obtain explicit consent (opt-in) from subscribers before sending any email communication.
- Maintain List Health: Implement rigorous list hygiene practices, including regular cleaning to remove invalid addresses and unengaged subscribers.
- Implement Full Authentication: Configure SPF, DKIM, and DMARC to authenticate your sending domain and improve deliverability.
- Warm-up New IPs: Gradually increase sending volume over time when using new IP addresses to establish a positive sender reputation.
- Monitor Feedback & Reputation: Actively monitor feedback loops, blocklists, and sender reputation metrics to identify and address deliverability problems promptly.
- Transparency and Honesty: Use clear, honest subject lines and make the unsubscribe process easy and transparent.
- Take Proactive Ownership: Take ownership of your deliverability practices, understanding that you play a critical role alongside your ESP.
- Adhere to RFC Standards: Emails adhere to RFC standards and any changes to formats should be closely reviewed prior to implementation to ensure no compliance issues.
What email marketers say
32 marketer opinions
The provided answers highlight numerous examples of bad email deliverability advice. These range from technical errors, such as neglecting email authentication and using invalid email formatting, to poor list management practices like buying email lists and sending to unengaged users. Other common mistakes include using misleading subject lines, ignoring complaint feedback loops, and failing to monitor blocklists. A recurring theme is the importance of obtaining explicit consent, maintaining a clean email list, and managing sender reputation proactively.
Key opinions
- List Hygiene: Buying email lists or failing to clean existing lists leads to deliverability issues due to spam complaints and invalid addresses.
- Permission: Sending emails without explicit consent damages sender reputation and increases the likelihood of being marked as spam.
- Authentication: Neglecting email authentication protocols (SPF, DKIM, DMARC) makes emails appear suspicious, negatively impacting deliverability.
- Sending Volume: Sending high email volumes from new accounts or without warming up can trigger spam filters.
- Misleading Tactics: Using misleading subject lines or hiding unsubscribe links harms sender reputation and increases spam complaints.
- Feedback Loops: Ignoring complaint feedback loops and blocklists prevents identifying and addressing deliverability problems.
- Content: Using spam trigger words in email content reduces the chances of the email reaching the intended recipient.
Key considerations
- Obtain Consent: Always obtain explicit consent from recipients before sending emails to comply with anti-spam laws and maintain a positive sender reputation.
- Maintain List Hygiene: Regularly clean your email list to remove invalid addresses and unengaged subscribers to minimize bounce rates and spam complaints.
- Implement Authentication: Implement SPF, DKIM, and DMARC to authenticate your emails and improve deliverability by verifying your identity to email providers.
- Monitor Reputation: Actively monitor your sender reputation and address any issues promptly to maintain good deliverability rates.
- Provide Clear Unsubscribe: Always include a clear and easily accessible unsubscribe link to allow recipients to opt out and reduce spam complaints.
- Test and Monitor: Consistently test email deliverability, check for spam trigger words and ensure a clear process for complaints or unsubscribes are adhered to.
Marketer view
Email marketer from Active Campaign shares that not including a clear unsubscribe link in your emails will lead to higher spam complaints and will negatively affect your sender reputation.
13 Jan 2024 - Active Campaign
Marketer view
Marketer from Email Geeks shares bad deliverability advice: "You can buy lists as long as you send an opt out pass first so that anybody who doesn't want your content can just excuse themselves!"
14 Jul 2024 - Email Geeks
What the experts say
6 expert opinions
The provided expert advice highlights several pitfalls in email deliverability strategies. These include ineffective suppression strategies (focusing solely on non-clickers), relying on quick fixes like switching ESPs for blocked IPs, and using outdated or risky techniques like hash busting. Additionally, neglecting feedback loops from ISPs, assuming deliverability is solely the ESP's responsibility, and failing to manage email lists properly (including handling bounces and removing inactive subscribers) are detrimental to email deliverability.
Key opinions
- Suppression Strategies: Prioritizing the suppression of non-clickers over non-openers is not an effective deliverability strategy.
- Switching ESPs as a Solution: Switching ESPs immediately after IP blocking is a temporary solution that does not address the underlying deliverability issues.
- Hash Busting: Using hash busting techniques is an outdated practice that can harm deliverability and sender reputation.
- Ignoring Feedback Loops: Neglecting complaint feedback loops from ISPs prevents senders from identifying and addressing deliverability problems effectively.
- Shared Responsibility: Assuming deliverability is solely the ESP's responsibility leads to neglect of essential sender-side practices.
- List Management Neglect: Failing to manage email lists properly, including handling bounces and removing inactive subscribers, harms deliverability.
Key considerations
- Refine Suppression: Develop refined suppression strategies based on both open and click data to improve engagement metrics.
- Address Root Causes: Instead of switching ESPs immediately, address the root causes of IP blocking to improve sender reputation and prevent future issues.
- Avoid Outdated Techniques: Avoid using outdated and risky techniques like hash busting, which can negatively impact deliverability.
- Monitor Feedback Loops: Actively monitor complaint feedback loops from ISPs to identify and remove users complaining about your emails.
- Take Ownership: Take ownership of your deliverability by actively managing your sending practices and reputation.
- Maintain List Health: Regularly clean your email lists by removing inactive subscribers and handling bounces to improve deliverability.
Expert view
Expert from Email Geeks shares bad deliverability advice: "Suppressing non-clickers is even more effective at improving delivery metrics than suppressing non-openers."
6 Jul 2021 - Email Geeks
Expert view
Expert from Spam Resource explains that ignoring complaint feedback loops from ISPs is bad deliverability advice. Complaint feedback loops allow you to remove users complaining and improve deliverability.
11 Jan 2025 - Spam Resource
What the documentation says
4 technical articles
The provided documentation highlights critical technical aspects affecting email deliverability. Drastic changes in sending volume without proper IP warm-up can trigger spam filters. Ignoring feedback loops (FBLs) prevents identifying and addressing spam complaints. Invalid email formatting and headers violate standards, leading to deliverability issues. Failing to monitor blocklists results in a poor IP and domain reputation, harming overall deliverability. All these factors contribute to decreased inbox placement and sender reputation.
Key findings
- Volume Spikes: Drastically changing sending volumes without warming up IPs can trigger spam filters.
- Feedback Loop Neglect: Failing to monitor and act on feedback loops prevents identifying and addressing spam complaints.
- Format Violations: Sending emails with improperly formatted headers or invalid email addresses negatively impacts deliverability.
- Blocklist Ignorance: Failing to monitor blocklists results in poor IP and domain reputation.
Key considerations
- Warm-up IP: Gradually increase sending volume when using new IP addresses to establish a positive sender reputation.
- Monitor FBLs: Actively monitor and respond to feedback loops to identify and remove spam complainers from your list.
- Adhere to Standards: Ensure all emails adhere to RFC standards for formatting and validation of email addresses.
- Monitor Blocklists: Regularly check if your IP address or domain is on any blocklists and take steps to get removed if necessary.
Technical article
Documentation from RFC explains that sending emails with improperly formatted headers or invalid email addresses can negatively impact deliverability. Adhering to email standards is crucial for avoiding spam filters.
4 Jul 2024 - RFC
Technical article
Documentation from Sparkpost shares that failing to monitor blocklists results in poor IP and domain reputation which hurts your overall email deliverability.
19 Mar 2022 - Sparkpost
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