Newsletter Crew July 14, 2020

List cleaning and email tracking blockers?

Aaron Nesmith-Beck @anesmithbeck

I understand it's good practice to clean your email list of unresponsive subscribers, but what about people using email tracking blockers?

Presumably someone using a tracking blocker could be reading every single email I send them, yet still show up with a 0% open rate.

Or am I missing something here? Any thoughts or suggestions are appreciated. Thanks!

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    I think what you should do here is send a re-engagement email (hey! do you still want to be on this list?) before removing inactive subscribers.

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    That’s a great question. We talked about that here in the comments.

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    Hey Aaron. Yes that is a small problem. For example and there are other few privacy focused. Since they are paid emails clients they represent very small %. For example you could tag and filter out Hey emails and keep them on the list. It wont be a lot. The biggest part is Gmail, Outlook and Yahoo, Hotmail and they don't block anything.

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    There's no way to know who is using a tracker blocker or not (by virtue of a tracker blocker) so before cleaning a list, I do a re-engagement sequence that gives folks a chance (and a motivation) to take action before removing them from the list.

    I wrote a super detailed guide to how I do it for our list, and what to avoid, and how the numbers actually work out for us:

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      Reading it now, thanks!

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    Check out Obviously I'm biased, but imo it's a better way to do list cleaning.

    Readers who use plain text and have disabled HTML emails will also show up with a 0% open rate.

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      Thank you!

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      If you're regularly sending emails, won't most of these already be filtered out by the ESP? Not sure there are any ESP's who allow invalid emails to remain in the list.

      How does it help with inactive subscribers?

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        From my experience most ESPs only care about the hard bounced email addresses to protect their IPs. They won't remove them, either, but rather suppress sending email addresses to them. And most ESPs charge by number of contacts.

        The question is regarding list cleaning, which helps with email deliverability, domain reputation, as well as inactive subscribers. For example, some ESPs will not allow certain domains like, but some will. Some won't allow role based email addresses like [email protected], but some will. And almost all that I know of will allow disposable email domains, and they will continue to get delivered but not opened. At lower volumes none of this is that big of a deal but at higher volumes this matter quite a bit, especially if the ESPs start sending you account warnings or suspending your account outright. Removing inactive subscribers based on the open-rate could be removing a lot of happy subscribers who simply have tracking blockers enabled or plain-text only enabled.

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          You're right they won't remove them, per se. However they will change the status and won't charge you for those contacts. I'm not aware of any ESP who charges for a contact who remains in a hard-bounced status. For example, Mailchimp set them as cleaned. Mailerlite bounced. Convertkit bounced. We unsubscribe them. None of us charge though.

          The point you make about typos and disposable mails is one I hadn't considered, and could be a good way to remove a handful subscribers from the unopened. Though I'm not sure it'll solve the broader impact that lack of engagement will have on deliverability.

          My suggestion would be to use a combination of clicks and opens to ascertain engaged subscribers.

          Then for this un-engaged run a re-engagement campaign, before unsubscribing them. If you're concerned they have tracking blockers or are using plain text I'd suggest using a link click to signal they want to continue to receive emails.

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            Some ESPs allow contacts without email addresses in them, but some don't. For those that don't there are customers that use them as CRMs as well, and what I've seen is that the customers will enter a fake email address. These contacts are still being charged to be stored in them because of the other associated data. Ideally, they should be pre-emptively put into an unsubscribe or suppression status before accidentally sending an email to them (a contrived example and a small use case, I know).

            I agree with you on observing clicks and opens as a general rule of thumb and for certain domains, but I think where we differ in philosophy is you are suggesting a more active approach, but I'm suggesting a more passive approach.

            In my opinion, sending a re-engagement campaign to inactive subscribers (who are actually active) is annoying and a good way of turning them off. subscribers, for example, would be forced to click a link every time the re-engagement campaign runs for no other reason except that they use a Hey email address. I can't imagine they'd stick around long.

            There is a middle-ground, I think, where you choose to send re-engagement campaigns for certain domains while also relying on a list cleaning service to do a lot of the heavy lifting that automates the typo fixing, removing invalid email address, tagging them for automations/segmentation/reporting, etc.

            P.S. I'd love to integrate with Email Octopus, but there are some missing pieces of the API that prevent us from doing so. I did reach out to you guys earlier this year to make some feature requests :)

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              From both a deliverability and cost approach, an active approach to list management is important. So I think it's important to discuss what a well run re-engagement campaign looks like. As in my experience it wouldn't result in you needing to opt-in every-time.

              If we were to do a re-engagement campaign on users who had shown no activity, we would set an attribute or tag on any user who does request to continue to receive emails. Then the next time a 'clean' is done you'd exclude: recent opens, recent clicks or tag set. I agree you don't want to be penalising or annoying users for using a particular mailbox provider.

              There's definitely a time and place for list cleaning, but I think that's mainly when you're not sending at irregular intervals or have an old list.

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                You bring up some great points that are hard to argue and I'm mostly in agreement with. The only disagreement would be your last point on list cleaning. I do think traditional list cleaners are quite painful to use which is the problem I aimed to solve for myself and why I think people don't really bother with it.

                However, if you're sending at scale, getting a lot of spam signups or typos, to prevent list decay, and so on, regular list cleaning is important. Even real-time at point of entry via API if you're inclined. Our best customers are the ones who definitely need list cleanliness and data quality to scale their email campaign efforts.

                I guess this could go back to the whole double versus single opt-in debate. There really is no right or wrong but a matter of preference and testing to see what works for your business.

                I love nerding out about this stuff. I read an interesting article yesterday that you might find interesting regarding email deliverability -