Case Study: Inside an Email Deliverability Report for a CBD Brand

At Cannascale, we regularly audit and optimize email deliverability for our clients because poor inbox placement can quietly erode the effectiveness of even the best email marketing strategy. Recently, we conducted a deep dive into the email performance of a new client in the CBD space who was struggling to see results despite having a large email list. Their campaigns and flows weren’t performing as expected, and their revenue from email had plateaued. The culprit? A major deliverability issue, particularly with Gmail and Apple inboxes.

In this breakdown, we’ll walk through our findings, the impact of engagement on deliverability, and the step-by-step repair plan we implemented to get their emails back in front of their customers. If you’re seeing declining open rates or struggling with email performance, this case study will highlight the importance of maintaining a strong sender reputation and what you can do to fix it.

Let’s dive in.

‍

The Problem: A Big List with Low Engagement

Our client came to us with a seemingly strong email marketing foundation—a large list of subscribers and regularly scheduled campaigns. However, their performance was declining, with many emails failing to reach inboxes, particularly in Gmail and Apple Mail. Despite their list size, they weren’t achieving the sales results they expected.

The culprit? Poor email deliverability, largely driven by sending to unengaged subscribers.

‍

Step 1: Inbox Placement Breakdown

The first step in any deliverability audit is checking inbox placement across major providers. Here’s what we found:

• Gmail inbox placement: 22% (critical issue)
• Apple inbox placement: 23% (critical issue)
• Verizon (Yahoo/AOL) inbox placement: 64% (healthy)
• Microsoft (Outlook/Hotmail) inbox placement: 41% (low)

Gmail made up 62% of the brand’s active email list, making it the most critical issue. Apple Mail had a much smaller percentage of users, but still showed deliverability struggles.

‍

‍

Step 2: List Health & Subscriber Engagement

A deeper look into the Klaviyo account revealed the list breakdown:

• Total profiles in Klaviyo: Over 222,000
• Active profiles: 98,000
• Suppressed (inactive) profiles: 125,000

Breakdown of active list inbox providers:

• Total active profiles able to receive email - 98,000
• Gmail  62,000 (62%)
• Apple 2,000 (1.9%)
• Verizon 18,500 (18%)
• Microsoft 8,000 (8.4%)
• The remainder including Google Workspace and Outlook business (9%)

Never Engaged Segment

One of the biggest warning signs in any email marketing strategy is a high percentage of unengaged subscribers. We created a segment of users who had:

• Been on the list for 90+ days
• Never opened or clicked an email
• Never placed an order
• Received at least 10 emails in the last 90 days

This “never engaged” segment contained 52,000 profiles (53% of the active list).

Sending emails to unengaged subscribers is a fast track to poor deliverability, especially with Gmail. Email providers prioritize engagement, and consistently emailing inactive contacts can tank your sender reputation, sending more of your messages straight to spam.

‍

Step 3: Campaign Performance Analysis

We reviewed recent email campaigns and found that many had open rates below 50%, with some dipping as low as 16%. While a mix of high and low open rates is standard, consistently poor engagement signals to email providers that your messages aren’t valuable—reducing inbox placement over time. Google is very sensitive to the CBD space, and when it sees low engagement rates, it can move against domains quite unexpectedly.

‍

‍

As you can see from the chart below, campaigns have experienced low open and click rates over the last 30 days. We must improve these stats to improve deliverability and reach more inboxes.

‍

‍

To confirm this, we ran a deliverability test using GlockApps, a leading email testing tool. The results were concerning:‍

• ‍Overall deliverability score: 37% (should be 60-80%)
• 58% of test emails were flagged as spam (mostly Gmail and Microsoft)

‍

‍

The Fix: Cannascale’s Deliverability Repair Plan

The usual repair plan centers around really tightening up segments and removing those that are not engaged from most sends. We institute a plan where we send to the very most engaged until we see a bump in deliverability. Then, we slowly widen those sending segments to the slightly less engaged. As our sending reputation improves, we widen them further to the less engaged, constantly monitoring and adjusting the segments we send to.

Klaviyo has just released an AI tool to help with the process. Because poor deliverability impacts their ability to deliver emails for all of their clients, they are making it a part of their sending procedures and removing emails they consider unengaged from sends while their reputation remains low.

• For now, use the Never Engaged All Time segment as an exclusion segment on all campaigns to stop sending them to those who have never engaged.
• Exclude the Bounce segment from all sends (Will catch and stop emails that bounce multiple times)
• Continue working with Klaviyo AI Deliverability Repair Tool when sending campaigns.
• As deliverability improves, use a Sunset Flow to slowly send a last-chance re-engagement email to the less engaged on a metered basis to prevent further impact on deliverability.
• Suppress the totally unengaged. You are currently paying to have these profiles in the account each month, and with all the sends that have been done to these profiles, they have never engaged, and based on experience, they will never engage. A lot of them will be bots and other nuisance traffic, so suppressing them will have no impact on sales, but stopping sending repeatedly to them will improve deliverability, and reducing the profiles in the account will save each month in Klaviyo fees.

Given our deliverability issues, and as suggested by the Klaviyo AI repair tool, it would be worth connecting to a Klaviyo-integrated service like Kickbox to clean and verify the lists. Kickbox will scan the list and check each address to ensure it exists and can be delivered. More importantly, services like this maintain huge lists of bot-generated email addresses and other bad addresses and will check your lists against those, flagging any that should be removed from your lists.

You can read about the integration between Kickbox and Klaviyo here: https://docs.kickbox.com/docs/integrating-with-klaviyo

‍

Step-by-Step Summary of our Deliverability Repair Plan

Stop Sending to the Unengaged

• Use the Never Engaged segment as an exclusion list for all campaigns
• Exclude bounce-prone profiles to prevent further damage to sender reputation
• Leverage Klaviyo’s AI Deliverability Repair Tool for smarter sending

Implement a Re-Engagement & Sunset Flow

• Design a last-chance campaign for slightly disengaged subscribers
• Suppress fully unengaged contacts (reducing Klaviyo costs and improving list quality)

Monitor & Adjust Sending Strategy

• Closely track Klaviyo send stats to refine segmentation
• Set up Google Postmaster Tools to monitor Gmail domain reputation

Audit & Optimize Domain Authentication

• Review Shopify and third-party apps to ensure proper email authentication. These days, many third-party apps installed on platforms like Shopify also send emails on your behalf. Some of those apps, such as shipping services or review platforms, quite often have setup steps that include getting authenticated on your domain so they can send properly authenticated emails. Sometimes, those steps are missed or overlooked, leading to emails from these platforms not being properly authenticated, which will also cause issues with deliverability.
• Set up DMARC monitoring to detect potential spoofing or malicious activity

Use List Cleaning Tools

• Recommend Kickbox to verify email addresses and remove invalid or bot-generated profiles

‍

How Long Does Deliverability Repair Take?

Gmail doesn’t reveal how long it takes to recover sender reputation, but with the right fixes, we typically see improvements within 2-4 weeks. In about 6-8 weeks, we can begin opening up the segments. It’s hard to say how long full recovery can take, but oftentimes around 8-12 weeks, following a strict recovery plan, many brands can expect a full recovery.

Like all things with Google, there is no specific time frame on deliverability repair, but one thing is certain if we do not take action now, deliverability will continue to slide to the point where domain reputation will crash and almost all emails sent to Gmail will end up in spam.

‍

Final Thoughts: Why Deliverability Audits Matter

If your brand relies on email marketing for revenue, deliverability is just as important as content and design. A well-optimized email program ensures that your emails actually reach customers and drive sales.

If your open rates are declining, your emails are landing in spam, or you suspect a deliverability issue, a full audit like this can reveal the root causes and get your email strategy back on track.

Update: Our client is already starting to see improvement, with a deliverability score of 71, +16 over the previous 30 days.

‍

‍

Need help? Reach out to Cannascale for a free deliverability consultation.