Category: List hygiene and subscriber quality

  • Optimize contact list deliverability

    Learn how to maintain a healthy contact list that improves your email deliverability and sender reputation.

    What is Email Deliverability?

    Email deliverability is the ability to successfully deliver emails to your subscribers’ inboxes. A well-maintained contact list is essential for ensuring your messages reach their intended recipients rather than being marked as spam or bounced.

    Why List Optimization Matters

    Protect Your Sender Reputation

    Email providers track how recipients interact with your emails. High bounce rates, spam complaints, and low engagement can damage your sender reputation, potentially causing future emails to be filtered or blocked, resulting in inconsistent deliverability.

    Improve Engagement Rates

    A clean, engaged list leads to better open rates and click-through rates. When you focus on contacts who actually want to hear from you, your campaign performance improves significantly.

    Maintain Compliance

    Keeping an updated list helps you stay compliant with email marketing regulations like GDPR. This protects both your subscribers’ privacy and your business reputation.

    Key Optimization Practices

    Remove Invalid Email Addresses

    • Hard Bounces – Immediately remove email addresses that hard bounce (permanent delivery failures). These addresses are invalid and will continue to hurt your deliverability if you keep sending to them after they are re-uploaded into your list, as our system automatically unsubscribes them from your list.
    • Syntax Errors – Check for and remove email addresses with formatting errors, missing @ symbols, or invalid domain names. These will never successfully receive your emails.

    Manage Inactive Subscribers

    • Identify Inactive Contacts – Use our advanced filters to find subscribers who haven’t opened or clicked your emails in 3-6 months. These contacts drag down your engagement metrics.
    • Re-engagement Campaigns – Before removing inactive subscribers, send a re-engagement campaign asking if they still want to hear from you. Give them a clear option to stay subscribed or opt out.
    • Remove Unresponsive Contacts – If subscribers don’t respond to re-engagement attempts, remove them from your regular sending list. You can keep them in a separate segment for occasional campaigns if desired.

    Validate Email Addresses

    • Use Double Opt-In – Implement double opt-in for new subscribers to verify their email addresses are valid and they genuinely want to receive your emails. This prevents fake or mistyped addresses from entering your list.
    • Regular Validation – Periodically validate your email list to identify addresses that have become inactive or invalid over time. This helps maintain list quality.

    Remove Spam Complaints

    • Monitor Complaints – Keep track of subscribers who mark your emails as spam. Remove these contacts immediately as continued sending will severely damage your reputation.
    • Understand Why – If you’re getting frequent spam complaints, review your email content, sending frequency, and signup process. Make sure expectations are clear when people subscribe.

    Segment by Engagement

    • Active Subscribers – Create a segment of highly engaged subscribers who regularly open and click your emails. These contacts should receive your most frequent communications.
    • Moderate Engagement – Segment subscribers who engage occasionally. Send them less frequently or with different content to maintain their interest.
    • Low Engagement – Keep low-engagement contacts separate and send them minimal, highly targeted content. Monitor for signs of renewed interest or continued disengagement.

    Using Sender’s Tools for Optimization

    Advanced Filters

    Navigate to Subscribers -> Segments and use advanced filters to identify contacts based on:

    • Campaign activity (opened, clicked, inactive)
    • Subscription status
    • Created date
    • Custom fields

    Regular List Audits

    Schedule monthly or quarterly reviews of your contact list:

    • Filter for inactive subscribers
    • Review bounce rates
    • Check for engagement patterns
    • Remove or re-segment as needed

    Optimization Schedule

    Weekly or Bi-Weekly

    • Remove hard bounces from your list completely
    • Process unsubscribe requests if any come through
    • Monitor spam complaints

    Monthly

    • Review engagement metrics
    • Identify inactive subscribers
    • Clean up obvious errors

    Quarterly

    • Run re-engagement campaigns
    • Remove unresponsive contacts
    • Validate overall list health
    • Update segmentation strategy

    Warning Signs Your List Needs Optimization

    • Open rates consistently below 30-35%
    • High bounce rates (above 5%)
    • Increasing spam complaints
    • Declining engagement over time
    • Large number of unsubscribes after sends

    Best Practices

    Set Clear Expectations

    Tell subscribers what they’ll receive and how often during the signup process. This reduces future complaints and maintains engagement.

    Monitor Metrics Regularly

    Keep an eye on your deliverability metrics including bounce rates, open rates, and spam complaints. Early detection of issues allows for quick corrections.

    Quality Over Quantity

    A smaller list of engaged subscribers is far more valuable than a large list of inactive contacts. Focus on maintaining quality rather than just growing numbers.

    Tips for Long-Term Success

    • Never purchase email lists – they damage deliverability and violate our Terms of Service, which will lead to your account’s suspension as well
    • Use consistent “from” names and email addresses
    • Maintain a regular but not excessive sending schedule
    • Personalize content to increase relevance and engagement
    • Test your emails before sending to catch potential issues

    That’s it!

    If you got stuck on a specific task or can’t find a way to execute a particular job, contact our support team via LiveChat or [email protected] – we’re here to help 24/7.

  • Keep subscriber list clean

    The main reason to keep your list clean is to maintain good deliverability and make sure that your campaigns reach your subscribers’ inboxes. Storing your unengaged subscribers also uses up your plan limits, therefore regularly cleaning up your subscriber list saves you money as well.

    How to filter out the unengaged subscribers?

    You should firstly identify what would you consider an unengaged subscriber as this highly depends on your campaign sending frequency. 

    If you send a campaign less than 4 times a month or during particular seasons you should filter out those subscribers that did not open any of your campaigns for the past year.

    If you send a campaign at least 4 times a month, filter out the ones that did not open a campaign for the past 6 months.

    Start by going to Subscribers  and click “Advanced filter”.

    By using the Advanced filter, set the conditions to match those of unengaged subscribers as explained previously.

    After that click “Save as a new segment” and name it accordingly.

    You can also focus on the subscribers that did not open AND did not click any link, which is another important indicator of recipients’ engagement. You should stay within the time frames as previously explained.

    After that click “Save as new segment” and name it accordingly.

    What to do with the unengaged subscribers?

    After identifying your inactive audience and putting them into a separate segment, you can either delete or unsubscribe them. You should choose one of these options, as keeping them in your list and in “Active” status will cause you to waste your Active subscriber plan limits.

    Unsubscribing the unengaged subscriber list allows you to still maintain the contact details of your unengaged audience but will not let you email them and their presence in your list will not use up your subscription plan limits.

    Deleting the unengaged subscribers will remove their information from the system. 

    That’s it!

    If you got stuck on a specific task or can’t find a way to execute a particular job, contact our support team via LiveChat or [email protected] – we’re here to help 24/7.