Clean your list every six months. Remove hard bounces immediately, remove role addresses like info and sales, and remove anyone who has not opened in twelve months after one re-engagement attempt. A list of two thousand engaged people outperforms ten thousand where eight thousand ignore you, because engagement is what decides whether the two thousand see you at all.
That last point is the one that makes cleaning worth the discomfort.
Why dead addresses cost you the live ones
Mailbox providers measure how recipients respond. A large block of people who never open drags your aggregate engagement down, and low engagement is a filtering signal applied to everything you send.
So the unengaged do not simply fail to read you. They actively reduce the chance that your engaged subscribers see you in their inbox rather than their spam folder.
You are also paying for them on most platforms, which is the smaller of the two costs and the more visible one.
Who to remove, in order
Work down this list; the top items are unambiguous and the bottom ones need a judgement call.
- Hard bounces: the address does not exist. Remove on the first bounce, always
- Repeated soft bounces: after three consecutive, treat as dead
- Role addresses: info, admin, sales, support. These are shared inboxes and generate complaints
- Obvious typos and disposable domains, which arrived through an ungated form
- Anyone who has not opened or clicked in twelve months, after one attempt to win them back
Run the re-engagement attempt properly
Before removing the long-dormant, send two or three emails over a fortnight that make it easy to stay or go.
Be direct about it. Say you have noticed they have not been reading, ask whether they want to keep hearing from you, and give one obvious button for yes. Do not dress it up as a normal newsletter, because the point is to force a decision.
Whoever responds is now demonstrably engaged. Whoever does not has told you something clear, and keeping them is a decision to prioritise a number over the people who read you.
Stop the problem at the form
Most list decay is caused at signup rather than over time.
Ungated giveaways attract people who want the file and nothing else. Prize draws attract people who want the prize. Pre-ticked consent boxes attract people who did not notice. All three produce large lists that behave like small ones.
Double opt-in reduces signups and improves nearly every subsequent number. It is worth it wherever your form attracts bot traffic or typos.
What to check before you delete
Two cautions, both learned expensively by other people.
Open rate is now unreliable as a sole measure of engagement, because privacy features on some mail apps mark messages as opened automatically and others suppress the signal entirely. Use clicks, replies and site visits alongside it rather than opens alone.
And check whether a segment is dormant for a reason. Customers who buy once a year are not unengaged, they are seasonal, and removing them is expensive.
What to expect afterwards
Your list size falls and every rate improves, because the denominator shrank and the remaining people actually want to be there.
Report the change honestly rather than quietly. A dashboard showing a smaller list and a higher open rate looks like a mistake to anyone who was not told, and the explanation is the whole point.
Common questions
- How often should I clean my email list?
- Every six months. Remove hard bounces immediately, remove role addresses like info and sales, and remove anyone who has not opened in twelve months after one re-engagement attempt.
- Does removing subscribers hurt my results?
- The opposite. Unengaged contacts drag your aggregate engagement down, and low engagement is a filtering signal applied to everything you send, so they reduce the chance your engaged subscribers see you at all.
- Is open rate reliable for deciding who to remove?
- Not on its own. Privacy features on some mail apps mark messages as opened automatically and others suppress the signal. Use clicks, replies and site visits alongside opens.
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