How to Improve Email Deliverability with Segmentation

Email deliverability is a critical metric for sales development representatives (SDRs), agencies, and freelance marketers who rely on large-scale email campaigns to reach their target audience. Poor deliverability can disrupt outreach efforts, reduce engagement, and negatively impact client relationships. However, with the right segmentation strategy, you can fix deliverability issues, improve engagement, and maintain inbox placement.

In this article, we’ll break down a transformative approach to email segmentation, highlighting actionable steps to achieve better open rates, maintain strong sender reputations, and optimize workflows. Whether you’re managing outreach for your team or working with clients, these insights will help you overcome the common barriers to successful email marketing.

Why Email Deliverability Matters

Before diving into the strategy, let’s address why email deliverability is so important. When emails fail to land in your audience’s inboxes (or worse, end up in spam), your campaigns lose their effectiveness. Deliverability is influenced by several factors, including email content, recipient engagement, and sender reputation.

Key indicators of deliverability issues include:

• Open rates consistently below 40%.
• High bounce rates or spam complaints.
• Poor performance with specific email providers (e.g., Gmail, Outlook).

By leveraging segmentation, you can address these issues at the root and create campaigns tailored to more engaged audiences.

Step 1: Diagnose Deliverability Issues

Before implementing a solution, it’s critical to determine whether your deliverability is truly poor. Gavin, an experienced email marketer featured in the video, suggests starting with a thorough review of your metrics.

Metrics to Monitor

1. Open Rates
   Open rates are a strong initial indicator of deliverability issues. Emails consistently getting below 40% open rates signal a problem. However, keep in mind that some email platforms may inaccurately report open rates due to privacy settings (e.g., Apple Mail Privacy).
2. Click Rates and Spam Complaints
   Low click rates and high spam complaint rates can also indicate disengagement and poor inbox placement.
3. Bounce Rates
   Check for soft and hard bounces. A hard bounce often signals invalid email addresses, while soft bounces may point to temporary issues.
4. Provider-Specific Performance
   Evaluate which inbox providers (e.g., Gmail, Outlook) are underperforming. Some providers may flag your emails more aggressively than others.

Step 2: Apply Bounce Filters to Your Flows

One of the simplest ways to improve deliverability is by filtering out invalid or disengaged email addresses from your active workflows.

How to Add Bounce Filters

For each active flow in your email platform:

• Add a profile filter that excludes recipients who have bounced emails in the last 30 days.
• This ensures you are not repeatedly attempting to contact invalid addresses, which can harm your sender reputation.

Pro Tip: Many email platforms, such as Klaviyo, automatically suppress hard bounces after multiple failed delivery attempts. However, adding this filter proactively improves your results faster.

Step 3: Create Segments Based on Engagement

Strategic segmentation allows you to target the most engaged audience while excluding users who are less likely to interact with your emails. This approach improves engagement rates (e.g., open and click rates) and, by extension, deliverability.

Key Segments to Build

1. 90-Day Engaged Customers
   These are recipients who have:
   • Opened or clicked an email.
   • Placed an order.
   • Been active on your website in the last 90 days.
2. 90-Day Engaged Non-Customers
   This segment includes non-buyers who have engaged with your emails or website in the last 90 days.
3. Bounced Email Segment
   Create a segment of users who’ve had at least one bounced email in the last 30 days. Exclude this group from all campaigns.

Adjusting Engagement Windows

If your open rates are still below 40%, tighten the engagement window. For example:

• Move from a 90-day engagement window to a 60-day window for even higher engagement.
• Conversely, if open rates exceed 50%, expand the engagement window to 120 days to include more people.

This dynamic approach allows you to balance deliverability and audience reach effectively.

Step 4: Address Provider-Specific Issues

Sometimes, deliverability issues are tied to specific email providers like Gmail or Outlook. If you notice poor performance with certain providers, take the following steps:

Create Provider-Specific Segments

• Build segments based on email domains (e.g., Gmail users).
• Tighten the engagement window for these segments (e.g., 30-day engagement instead of 90 days).

Use Plain Text Campaigns

• For problematic providers, send simple plain-text emails instead of HTML-heavy designs.
• Plain-text emails are less likely to get flagged and often have better inbox placement.

While plain-text emails aren’t a long-term solution, they can help rebuild sender reputation with specific providers.

Step 5: Monitor and Adjust Regularly

Email deliverability is not a "set it and forget it" process. Regularly review your metrics and adjust your segmentation strategy accordingly. Key thresholds to monitor include:

• Below 40% Open Rates: Tighten engagement windows (e.g., move from 90 days to 60 days).
• Between 40-50% Open Rates: Maintain your current strategy.
• Above 50% Open Rates: Expand engagement windows to include more recipients.

Active campaign management ensures your emails consistently achieve high engagement rates without compromising deliverability.

Key Takeaways

• Diagnose First: Analyze open rates, click rates, bounce rates, and provider-specific performance to identify deliverability issues.
• Add Bounce Filters: Exclude recipients with bounced emails from flows and campaigns to improve sender reputation.
• Segment Strategically: Focus on 90-day engaged customers and non-customers, adjusting windows based on performance.
• Address Provider Issues: Use plain-text campaigns and provider-specific segments for better inbox placement.
• Adjust Frequently: Continuously refine your segmentation strategy to maintain 40-50% open rates.

Conclusion

Improving email deliverability doesn’t require drastic changes but rather a thoughtful approach to segmentation and engagement. By diagnosing your issues, cleaning your lists, and targeting the right audience, you can achieve higher open rates and ensure your emails land where they matter most - your audience’s inbox.

Remember, consistent monitoring and adjustment are key to long-term success. Start implementing these strategies today to optimize your outreach efforts and deliver real value to your audience.

Source: "Never land in SPAM again with this STRATEGY" - Gavin Hewitson, YouTube, Dec 16, 2025 - https://www.youtube.com/watch?v=XivlSJb-_m4

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