Summary
Sending emails to low-quality lists (including purchased, outdated, unengaged contacts, or invalid addresses) harms sender reputation, leading to decreased deliverability and open rates, even for previously engaged subscribers. This occurs because these practices trigger spam filters, cause blocklisting, and may lead ISPs to pull delivered mail or defer delivery. Maintaining good list hygiene, proactively managing sender reputation, and prioritizing opt-in contacts are essential to avoid these negative impacts.
Key findings
- Sender Reputation Impact: Sending to bad lists damages sender reputation, affecting deliverability across all campaigns.
- ISP Filtering & Actions: ISPs may filter emails to spam, pull delivered mail, or defer delivery based on sender reputation and mail stream quality.
- Spam Filter Triggers: Unwanted emails and invalid addresses trigger spam filters.
- Blocklisting Risk: High volumes of invalid addresses can lead to blocklisting.
- Open Rate Reduction: Sending to low-quality lists can lower open rates even for higher-quality lists.
- Opt-in Importance: Using purchased lists harms reputation due to lack of opt-in.
Key considerations
- List Hygiene: Regularly clean and segment email lists to remove unengaged or invalid addresses.
- Engagement Monitoring: Monitor subscriber engagement and remove or suppress inactive users.
- Opt-In Practices: Only send to subscribers who have explicitly opted-in to receive emails.
- Reputation Management: Proactively manage and protect your sender reputation.
- Avoid Purchased Lists: Avoid using purchased email lists.
- Prioritize Good Lists: Consider sending to better lists first to potentially boost subsequent open rates.
- Spam Trap Avoidance: Take measures to avoid sending to spam traps.
What email marketers say
11 marketer opinions
Sending emails to low-quality or unengaged lists negatively impacts sender reputation, leading to decreased deliverability and open rates, even for previously engaged subscribers. Practices like purchasing lists, sending to invalid addresses, or neglecting list hygiene trigger spam filters and damage IP reputation, requiring significant time and effort to repair.
Key opinions
- Sender Reputation Impact: Sending to bad lists damages sender reputation, influencing deliverability across all campaigns.
- ISPs Filter to Spam: Poor list hygiene causes ISPs to filter emails to spam, impacting even engaged subscribers.
- Deliverability Decline: High bounce rates and low engagement lead to declining inbox placement.
- Open Rate Reduction: Sending lower quality emails first can lower open rates for higher quality lists.
- Gmail Pulls Delivered Emails: Gmail has been observed to pull already delivered emails out of the inbox if it detects issues.
Key considerations
- List Hygiene: Regularly clean and segment email lists to remove unengaged or invalid addresses.
- Engagement Monitoring: Monitor subscriber engagement and remove or suppress inactive users.
- Opt-In Practices: Only send to subscribers who have explicitly opted-in to receive emails.
- Prioritize Good Lists: Consider sending to better lists first to potentially boost open rates for subsequent sends.
- Segmentation Strategies: Segment and target emails appropriately to ensure relevant content is sent to engaged subscribers.
Marketer view
Email marketer from Litmus explains that sending emails to unengaged or bad email addresses can damage your sender reputation which will make it harder to deliver future emails to your users
6 Jun 2024 - Litmus
Marketer view
Email marketer from Neil Patel Digital explains that sending to a bad list hurts your sender reputation, which impacts deliverability rates of future campaigns to even good lists, as ISPs will view your IP address as a source of spam.
26 Feb 2022 - Neil Patel Digital
What the experts say
5 expert opinions
Sending emails to bad lists, characterized by poor hygiene, unengaged subscribers, or purchased contacts, can negatively impact sender reputation and deliverability. This can retroactively affect inbox placement, even for previously good lists. Some ISPs may pull delivered emails or defer delivery based on the perceived quality of the mail stream. Addressing poor list hygiene and actively managing sender reputation are essential for maintaining deliverability.
Key opinions
- Retroactive Impact: Sending to bad lists can retroactively hurt inbox placement of previously sent good lists.
- ISP Actions: ISPs may pull delivered mail or defer delivery based on the perceived mail stream quality.
- Microsoft's Role: Microsoft allegedly pulls delivered mail from inboxes.
- Sender Reputation Damage: Poor list hygiene practices negatively impact sender reputation.
- Spam Traps: Sending emails to known spam traps damages sender reputation, limiting delivery to valid users.
Key considerations
- List Hygiene: Maintain good list hygiene by removing unengaged or purchased contacts.
- Monitor Reputation: Actively monitor and protect your sender reputation.
- Avoid Spam Traps: Take steps to avoid sending emails to spam traps.
- ISPs Policies: Be aware of the different policies ISPs employ regarding mail stream quality.
Expert view
Expert from Word to the Wise explains that poor list hygiene practices, such as sending to unengaged or purchased lists, negatively impact sender reputation, resulting in deliverability issues for future campaigns.
26 Jan 2023 - Word to the Wise
Expert view
Expert from Email Geeks shares some ISPs will occasionally pull delivered mail out of the inbox if they change their mind about the mail stream. Others will defer delivery until they’ve seen enough mail to make a decision.
3 Jul 2023 - Email Geeks
What the documentation says
5 technical articles
Sending emails to bad lists, including invalid addresses, purchased lists, or unwanted recipients, can significantly damage sender reputation. This triggers spam filters, can lead to being placed on blocklists, and negatively impacts the deliverability of future emails, even to opted-in recipients. Resolving these issues often requires cleaning email lists and adjusting sending practices.
Key findings
- Spam Filter Triggers: Sending unwanted emails or emails to invalid addresses triggers spam filters.
- Blocklisting: Sending to many invalid addresses can place your server IP on blocklists.
- Reputation Damage: Poor sending practices damage sender reputation, impacting future deliverability.
- Impact on Opt-Ins: Deliverability issues affect even recipients who opted-in to receive emails.
- Cause of blocklisting: Being on a blocklist is probably due to sending spam-like emails or botnet infections.
Key considerations
- List Cleaning: Regularly clean your email lists to remove invalid or unwanted addresses.
- Sending Practices: Adjust sending practices to avoid triggering spam filters.
- Reputation Management: Take steps to protect and improve your sender reputation.
- Avoid Purchased Lists: Avoid sending to purchased email lists.
- ISP Communication: If blocklisted, contact your ISP and address the issues causing the listing.
Technical article
Documentation from Sparkpost explains that sending to purchased email addresses will damage your sender reputation which will make it harder to deliver future emails to your users
25 Jun 2022 - Sparkpost
Technical article
Documentation from Amazon Web Services explains that sending to non-existent email addresses will damage your sender reputation which will make it harder to deliver future emails to your users
14 Mar 2024 - Amazon Web Services
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