The first thing is to reduce the number of sendouts to this segment. For example, if you send a newsletter 3 times a week, this segment should receive only 2 or better, 1 per week. After some time you should validate the emails with a tool like ZeroBounce and filter out invalid email addresses - especially important in a B2B context. In B2C, it's ok but often not needed. After this you should create a "reactivation" automation. Send 1 email a week with special offers, more clickbait titles, and content that should add value and is likely to be opened and clicked. Do this for 4-5 emails. Keep all emails that at least opened. All others you can remove from regular marketing activities. Just recently I did this process for a big travel company with over 500k subs, and we could reactivate around 60k emails. Sadly, after just 2-3 months we saw activity drop again on those. The "sad" truth is that some contacts are just less active, and you can't send them too many emails without increasing unsubscriptions and inactivity.
Every email list faces the same problem at some point: A large segment of subscribers simply goes quiet. Quiet meaning doesn't open anymore. From experience, "80/20 reigns supreme as always," but more often than not, it is more <30% of subscribers that are really active. This normally leads to fewer clicks and, in the long term, worse delivery. Therefore, the same question always arises: Reactivate or remove contacts?
And the simple answer is: Both. But in the right order.
First: Step Back and Analyze
When subscribers go inactive, it often goes unnoticed, but if it is noticed, many teams panic and launch aggressive win-back campaigns. That’s usually the wrong first move. Instead, the number of sendouts to this segment should be reduced. As an example, if you normally send 2 or 3 newsletters per week, reduce to 1.
Less pressure often leads to better signals and a lower unsubscribe rate in these segments. Sending more emails usually increases unsubscribes and damages sender reputation. Inactive subscribers are often overwhelmed, not necessarily uninterested.
If you’re unsure how to structure your reactivation logic, segmentation, or automation flows, it’s worth reviewing your setup before taking action.
Book a short strategy session, and we can look at:
- Your segmentation structure
- Your inactivity thresholds
- And whether you’re losing deliverability or revenue without realizing it
Now back to the process.
Step 1: Validate Email Addresses (Especially in B2B)
Before running any reactivation campaign, validate your emails.
Use a tool like ZeroBounce or similar to fix the most common issues likeinvalid addresses, hard bounces, and filter out risky emails. This is especially important in B2B contexts. In B2C, validation is useful but often not critical. In B2B, outdated business emails are common due to job changes. Continuing to send to them harms deliverability and campaign performance. Clean data first. Reactivate second.
Step 2: Build a Focused Reactivation Automation
Once your list is cleaned and frequency reduced, create a structured reactivation sequence.
The approach that worked best for us:
- 1 email per week
- 4–5 emails total
- Stronger subject lines (curiosity-driven, some people would call it clickbait. But don't be too extreme)
- High-value, high-click probability content (could be strong discounts, or overall very unique and relevant content)
The goal is not to nurture slowly. The goal is to trigger action so these contacts want to engage regularly again.
Anyone who opens more than one reactivation email or clicks at least one will be re-added to the active newsletter list. Those who remain inactive after the full sequence can be removed from regular marketing campaigns. This will have costs, protects the sender's reputation and gives an overall better picture of the "power" of your subscriber base.
Real-World Example: 500,000 Subscribers
We recently applied this process for a large travel company with over 500,000 subscribers. We first removed low-engagement contacts from regular newsletter activities, then validated them and deleted all invalid emails from the system. After that we built a 5-week reactivation automation.
We were able to reactivate roughly 60,000 subscribers. For us active means opened at least one of the last 5 emails. However, and this is important, after 2–3 months, activity declined again among a portion of those reactivated users.
The Reality: Some Contacts Are Just Less Active
And this example just highlights a "sad" truth. Not every subscriber can be saved long-term, and some are just less active than others.
You also can't force engagement by increasing frequency, which usually leads to the opposite effect. The better approach is to have a segment that just get's less newsletter per week.
Conclusion: Re-Engage or Remove?
Large subscriber numbers look impressive, but inactive contacts distort the true performance KPIs, such as open and click rates. Using the framework we described, you can always remove invalid emails and also remove contacts that couldn't be reactivated. Contacts with long-term lower engagement should be targeted less frequently to reduce unsubscribes and protect the sender's reputation. That is the whole magic.
If you need help with that feel free to contact us for a free discovery call.
