Have you ever spoken to a Deliverability Consultant and been advised to “clean your lists” or “keep your list clean?”

When it comes to deliverability issues, this piece of advice is almost always included in my recommendations, even when there's a technical solution

In the email deliverability world, keeping a subscriber base clean and well-maintained often resolves a majority of inboxing issues.

The problem is that there is conflicting information online about what a clean list actually is.

So let me clarify it for you.

Common misconceptions: What “list cleaning” is NOT

Strangely enough, there are more wrong meanings than right.

• List cleaning is not using a “list cleaning” service.

List cleaning services attempt to identify disabled, non-existent or misspelled addresses for you to remove from any email sends.

It sounds good, but it is actually quite unreliable. Also, if you have deliverability best practices in place with your email service provider (ESP) — like utilizing confirmed opt-in for new signups, suppressing hard bounces, and maintaining regular engagement with your audience — you shouldn’t need this service as it is handled more efficiently by your sending practices.

• List cleaning is not suppressing unsubscribes, spam complaints, and hard-bounced addresses.

The reason that I am saying this is NOT a part of list cleaning is because it is best practice for ESPs to do this by default.

In fact, if your ESP is not already doing this, I would suggest moving to one that does. The majority of ESPs in the industry already do this as this is an expected practice.

• List cleaning is not purchasing only confirmed opt-in lists.

There is a misconception that you can purchase an opt-in list. You can’t. End of story.

Permission-based sending, which Ortto and most other ESPs require, can be commonly defined as sending to subscribers who have explicitly opted into receiving messages directly from the sender.

So you can see, a “purchased opt-in list” is not a real thing, at least according to me and my industry colleagues.

What is the actual goal of list clean up and why does it matter?

The real purpose of list cleaning is to protect your sending reputation by removing the long-term unengaged subscribers before they can cause damage. It is also meant to protect subscribers by honoring their perceived preference of lack of interest in your messages.

Major freemail providers like Gmail and Yahoo make spam filtering decisions based on the engagement of their subscribers with your email traffic.

If too many people are not even opening your email, eventually even your most engaged subscribers will no longer see your email in their inbox.

On top of that, there is a common practice with various mailbox and blocklist providers to take old, inactive mailboxes and turn them into spam traps (often called “recycled spam traps”).

No list cleaning service can catch these as only the providers that own them know which they are. They still look like normal, active addresses.

The only way to make sure these are not present in your list is to regularly clean out your lists.

So let’s talk about how to do just that.

Four steps to actually clean your lis

1. Manually unsubscribe all subscribers who have not engaged (at least opened an email) in 12+ months.

   1. These have grown too cold and too dangerous to re-engage. It’s time to let them go.

2. Identify those whose last engagement was between 6-12 months ago

   1. If you want to be extra assertive you can include those whose last engagement was 4-12 months ago

3. Plan and send a Preference Update re-engagement campaign

   1. This campaign should include three things:

      1. A clear call to action in the Subject Line around the purpose of the email

         1. Example: Update your preferences now to continue hearing from us

      2. A clear statement in the content advising that a lack of preference update will mean the subscriber will be automatically unsubscribed

      3. Unsubscribe and Preference Center Links elevated to the main body of content

4. After 48 hours from send, proactively unsubscribe all addresses that did not open or click the Preference Update link

Bonus tip: automate it and save yourself

While I would recommend doing this once or twice a year at the very least, the ideal solution here is to automate this within whatever ESP/marketing automation platform you use.

By automating it, you can also automate other earlier win-back attempts to help reduce the number of subscribers that reach this “sunset” point.

For those that still reach that point, the re-engagement will be more relevant and timely with the automation than it would be if you were to wait for the target date once or twice a year, where some subscribers might age completely out of winability.

In the end, it’s simply important to make sure you are doing this on a regular basis to protect your ability to consistently and reliably reach the inbox of your subscribers on a daily basis.