Brevo Email List Hygiene: How to Keep Your List Clean

The quality of your email list matters far more than its size. A list of 500 engaged subscribers will outperform a list of 10,000 inactive ones — in open rates, click rates, and more importantly, in deliverability.

List hygiene is the ongoing practice of keeping your Brevo contact database clean, accurate, and engaged.

Why List Hygiene Affects Deliverability

Mail providers like Gmail, Outlook, and Yahoo track how recipients interact with your emails. When you send to large numbers of contacts who never open, the signal to these providers is: this sender's content is not wanted. Over time, that signal damages your sender reputation and causes more of your emails — even to engaged subscribers — to land in spam.

Brevo monitors your sending statistics and can alert you when engagement drops below healthy thresholds. But the best approach is proactive hygiene, not reactive damage control.

Step 1: Remove Hard Bounces Immediately

A hard bounce means the email address doesn't exist or is permanently unreachable. Brevo automatically suppresses hard-bounced addresses — they won't receive future campaigns. But you should also clean them from your contact list entirely.

Go to Contacts → All Contacts and filter by "Email is Blacklisted." Export this list and then delete these contacts. Keeping them inflates your list size while providing no value.

Step 2: Monitor Soft Bounces

A soft bounce is a temporary delivery failure — the inbox is full, the server was temporarily down, or the message was too large. Brevo will retry soft-bounced emails automatically.

However, if a contact generates soft bounces repeatedly over multiple campaigns, it's worth removing them. A pattern of soft bounces can indicate an address that's being abandoned or is about to become a hard bounce.

Step 3: Identify and Manage Inactive Subscribers

Inactive subscribers are contacts who haven't opened or clicked any of your emails in the past 90–180 days. They're hurting your engagement metrics without benefiting your business.

Creating an inactivity segment in Brevo:

Go to Contacts → Segments → Create a Segment.

Set conditions:

• "Last email opened date" is more than 90 days ago
• AND "Number of emails opened" is less than 1 in the last 6 months

This segment gives you a list of your least-engaged contacts.

Step 4: Run a Re-Engagement Campaign

Before deleting inactive subscribers, give them one last chance. A re-engagement (or "win-back") campaign is a short series — sometimes just one or two emails — designed to get inactive contacts to open, click, or otherwise signal they still want to hear from you.

Effective re-engagement subject lines:

• "Do you still want to hear from us?"
• "We miss you — here's something special"
• "Last chance to stay subscribed"

In the final email of your re-engagement sequence, be explicit: "If you don't open or click this email, we'll remove you from our list in 7 days." This honest approach often prompts action from contacts who had simply been busy.

Step 5: Remove Non-Responders

After your re-engagement campaign, contacts who still haven't engaged should be removed. This is not a failure — it's a data-driven decision that improves your metrics for everyone who stays.

In Brevo, create a segment for contacts who received your re-engagement campaign but did not open any email in the series. Delete or unsubscribe these contacts.

Step 6: Prevent Bad Addresses at Signup

The best list hygiene is stopping bad data from entering your list in the first place.

Use double opt-in. Brevo supports double opt-in (also called confirmed opt-in), where subscribers receive a confirmation email and must click a link before they're added to your list. This eliminates typos, fake addresses, and anyone who didn't genuinely opt in.

Enable double opt-in in Contacts → Subscription Forms for each form, or in Settings → Email for global opt-in settings.

Use an email validation service for any large list imports. Tools can check each address for validity before it enters your Brevo database.

How Often Should You Clean Your List?

For most businesses sending weekly or bi-weekly campaigns, a quarterly list audit is sufficient. Check your:

• Hard bounce suppression list
• Unsubscribe rate trends
• Open rate trends (a declining trend suggests growing inactivity)
• Spam complaint rate (should be below 0.1%)

Make list hygiene a scheduled task — add it to your calendar as a quarterly reminder.

Brevo Pricing at a Glance

All plans include unlimited contact storage. See full pricing on Brevo →