I’ve inherited a list of 20k subscribers that hasn’t been mailed in over 8 months. I know there are likely many dead addresses or "spam traps" in there. What’s the safest way to re-engage them or scrub the list so I don't get my domain blacklisted when I start sending again?
3 answers
Do not just hit "send" to the whole list! First, run the entire CSV through a verification service like NeverBounce or ZeroBounce. This will remove the hard bounces and known spam traps without you having to send a single email. After that, send a very simple "re-permission" campaign to the remaining "valid" addresses. Ask them if they still want to hear from you and offer an incentive. Be prepared to lose about 30-50% of the list, but remember: a smaller, engaged list is much more valuable for your deliverability than a large, dead one.
Would you recommend doing this re-engagement in small batches over a week, or is it better to just get the "breakup" email out of the way all at once?
I always use a "Sunset Policy." If they haven't opened in 6 months, they get one last "Goodbye" email, and if they don't click, they are automatically unsubscribed.
Elizabeth, that's the gold standard for list health! Karen, following a strict sunset policy will save you so much stress with your sender score in the long run.
Paul, definitely batch it! If you send to 20k stale leads at once and get a 5% bounce rate, your ESP might suspend your account. I’d limit it to 1,000 per day. This "warms up" your IP again and lets you monitor the feedback loop in real-time. If you see high complaints in the first batch, you can stop and pivot your strategy before the damage is permanent.