Cleaning your email list is one of the most effective ways to improve your deliverability, but it can feel counterintuitive to delete subscribers you worked hard to get. The goal is to shift your mindset from list size to list quality. A smaller, more engaged list will always outperform a larger, inactive one because it helps you build a better sender reputation with inbox providers like Gmail and Outlook. That reputation is the foundation of good deliverability.
Who exactly should I remove from my list?
You should focus on chronically unengaged subscribers. The first step is defining what "unengaged" means for your brand. On an episode of Honest Ecommerce, Nikita Vakhrushev made it simple: he suggests focusing on suppressing their audiences, meaning people who are not opening your emails. You can start by building a segment in Klaviyo of anyone who hasn’t opened or clicked an email in the last 90 or 120 days. The goal is to stop sending emails to "dead inboxes" that are no longer monitored.
Claus Lauter of Ecommerce Coffee Break adds another layer, suggesting you can segment by subscription date, since contacts who subscribed a long time ago and aren't engaging are prime candidates for removal. As Andriy Boychuk pointed out on the same show, many marketers are scared to do this, but it’s essential for list quality and even saves you money on your Klaviyo bill.
What's the actual process for cleaning the list?
This should be a regular, recurring process, not a one-time event. Claus Lauter recommends cleaning your list every 30 to 90 days. The first step isn’t immediate deletion, but an attempt to reactivate users with a re-engagement or "win-back" campaign. This involves sending a targeted campaign, maybe with a special discount or bonus, to your unengaged segment to see if you can get them to open or click. It’s your last-ditch effort to get a response.
After that campaign, anyone who still hasn't engaged can be moved to a suppression list. Nikita Vakhrushev walked through this process, explaining that you should exclude these people from future sends. Over time, you can then delete them entirely from Klaviyo. This methodical process ensures you give subscribers a chance to stay before you remove them for good, while actively improving your list health.
Why does this improve deliverability so much?
It all comes down to your sender reputation. When you repeatedly send emails to people who never open them, inbox providers (ISPs) like Gmail take notice. They see that a percentage of your recipients aren't interested, which signals that your content might not be valuable. As Ross Kramer, the CEO of email service provider Listrak, explained on Ecommerce Conversations, this directly damages your sender score, making it more likely that your future emails get routed to the spam or promotions folder for your entire list, even the engaged subscribers.
By cleaning your list, you're sending a powerful positive signal to those ISPs. You're showing them that you only send emails to people who want to receive them. This discipline results in higher engagement rates across the board, which protects your sender reputation and is a critical factor for strong inbox placement. This is how you ensure your marketing messages actually get seen.
Is there anything else I should do besides just removing people?
Yes. List hygiene is critical, but it works best when your technical foundation is also solid. Many experts, including Daniel Reifenberger on The eCommerceFuel Podcast, emphasize that you need to have the right authentication in place. This means ensuring your email authentication protocols like SPF, DKIM, and DMARC are set up correctly for your sending domain.
Think of it this way: DKIM and DMARC are what prove to email providers that your messages are legitimate and that you are who you say you are. Nikita Vakhrushev described this as a foundational step you must take alongside cleaning your lists. If you're sending from a domain that isn't properly authenticated, ISPs are suspicious from the start. Combining a clean, engaged list with proper technical credentials is the formula for great deliverability.
Ultimately, cleaning your list isn't about shrinking your audience, but about building a stronger, more profitable one. It’s a strategic decision to focus on the subscribers who are actually driving your business forward. By combining consistent list hygiene with a proper technical setup, you build a powerful and resilient email program that lands in the inbox and generates revenue.
