How to re-engage an old email list without hurting your deliverability

You've got a list you haven't emailed in a long time. Maybe the newsletter stopped, the shop went quiet for a season, or you changed email tools and never moved everyone over. Now you want to send again.

Sending to the whole thing at once is the riskiest move you can make. Here's how to do it safely.

Why an old list is risky

Two things happen to a list while it sits unused:

• Addresses die. People change jobs, close inboxes and stop using old accounts. Send to them and they bounce.
• People forget you. Someone who signed up two years ago may not recognise your name. Some of them will hit "Report spam" instead of "Unsubscribe".

Inbox providers like Gmail watch both. A burst of bounces and spam complaints from one sender tells them something's wrong, and your mail starts landing in spam. Your email platform watches too, and may pause your account.

The fix isn't complicated. It's mostly about order.

1. Clean the list before anything else

Export the whole list from your email tool and run it through a verifier. This takes out the addresses that will bounce before they can do any damage.

With ListBouncer you upload the CSV and get back:

• Safe: confirmed by the mail server. Your clean list.
• Major provider: Yahoo, Outlook, Hotmail and AOL, in their own download, because those providers don't let anyone confirm a mailbox.
• Will bounce: dead mailboxes, dead domains and throwaway addresses. Remove these from your email tool.
• Risky and Unknown: leave these out of your comeback sends.

If you're not sure the list is that bad, try a handful of addresses in our free email checker first. On an old list, it usually is.

2. Split what's left by how recently people engaged

Most email tools show when each person last opened or clicked. Use it to split the clean list into groups:

• Engaged in the last 6 months
• 6 to 12 months
• Over a year, or never

If your tool doesn't have this data (say you've changed platforms), split by sign-up date instead.

3. Start with the warmest group

Send your first email to the most recent group only. They're the most likely to open, and good opens early on tell inbox providers you're a sender people want to hear from.

Wait a few days. Check the bounce rate and spam complaints. If the bounce rate is well under 2% and complaints are close to zero, move to the next group.

4. Send a "do you still want these?" email

For the older groups, don't jump straight into a sales email. Send a short note first:

• Remind them who you are and how they signed up
• Tell them what you'll be sending and how often
• Make staying on the list one click, and leaving one click too

Something like:

You signed up for our newsletter a while back, and we've been quiet. We're starting again next week with one email a month: new products, a tip or two, and early access to sales. Want to stay on the list? You don't need to do anything. If not, the unsubscribe link is at the bottom and we won't take it personally.

An easy unsubscribe is your friend here. Every person who leaves quietly is one who won't mark you as spam.

5. Let the non-responders go

After two or three emails, some people still won't have opened anything. Stop emailing them. Most email tools can do this automatically after a set number of months.

It feels like losing subscribers. It isn't. People who never open don't buy, but they do drag down the numbers inbox providers use to decide where your mail goes. And most email platforms charge by contact count, so a smaller, engaged list can also cost less.

6. Do the Major provider list last

Yahoo, Outlook, Hotmail and AOL addresses can't be confirmed in advance. Send to them once your first few sends look healthy, as their own segment. If bounces come back, you'll know exactly where they came from.

Don't let it happen again

The easiest way to keep a list healthy is to keep using it. Even one email a month stops addresses from going stale unnoticed. And clean it every few months. See how often to clean your email list for a simple schedule.

If your platform has already flagged your account, start with what to do when your email platform flags you for bounces. And to see how accurate ListBouncer's checks are, take a look at our accuracy test.