Database Hygiene
A clean contact database is a sender reputation requirement, not a nice-to-have. Sending to invalid addresses, repeat hard bounces, or addresses harvested without proper consent will damage your domain reputation faster than any legitimate volume can rebuild it.
This page covers the three operational practices that keep the database healthy.
1. Periodic database cleansing
Mailtarget offers a Database Cleansing service that scans the Contact Book and flags addresses that should be removed or deactivated. The service is request-based, not self-serve in the dashboard.
The flow:
- Submit a request. Contact the Mailtarget support team and ask for a database cleansing run. The technical team handles the scan with a separate validation tool.
- Receive the report. The team returns a list of contacts flagged for removal or deactivation, focusing on hard bounces, role addresses (
info@,support@), spam traps, and addresses that fail SMTP-level verification. - Apply the recommendations. Remove or deactivate the flagged contacts in the Contact Book.
Run cleansing on a schedule. Quarterly is typical for high-volume accounts; monthly for accounts that experience rapid list growth or migrate from another provider.
A list that has gone six months without cleansing is statistically certain to contain dead addresses. Sending to those addresses produces hard bounces, hard bounces feed back into the suppression list, and the bounce rate damages reputation. Periodic cleansing breaks the cycle.
2. Engagement monitoring
Beyond hard bounces, segment by engagement state. Contacts that produce zero opens and zero clicks across multiple campaigns over a defined window (commonly 90 to 180 days) are functionally inactive. They contribute volume but not engagement.
Three ways to handle inactive contacts:
| Action | When |
|---|---|
| Re-engagement campaign | First time a contact crosses the inactivity threshold. One pass to confirm whether they want to keep receiving. |
| Suppress further sends | After re-engagement fails. Mark inactive in the Contact Book; exclude from future campaigns through a segment filter. |
| Hard delete | Only if account-level hygiene policy requires it. Most teams keep inactive records for analytics and compliance audit. |
Build the inactive segment as Status = Active AND Last open before <date>. See Segmentation.
3. Opt-in quality at the source
The cheapest hygiene is the hygiene that never has to happen. Capture clean data at intake.
Recommendations:
- Use double opt-in for marketing lists. A confirmation link drops bots, mistypes, and low-intent signups before they enter the active list.
- Validate email syntax at the form layer. RFC 5322 syntactic validation catches typos at submit time.
- Use Captcha on public forms. Captcha is a security control, not a friction tax. It protects against scraper-driven list poisoning.
- Avoid purchased or scraped lists. Mailtarget enforces a fair-usage policy. Repeatedly sending to lists with high bounce or complaint rates triggers account-level intervention. Read the fair-usage operations doc.
- Capture source attribution. Every form should add a label or custom field identifying where the contact entered. When a specific source produces high bounce rates, you can isolate it without affecting the rest of the list.
What ties hygiene to deliverability
Three signals propagate from hygiene to deliverability:
- Bounce rate. Low bounce rate keeps mailbox providers from down-ranking your IP and domain reputation. Bounce rate above 5 percent triggers automatic platform-level rate limiting.
- Complaint rate. Spam complaints are recorded as a webhook event. Repeated complaints lead to suppression. A complaint rate above 0.1 percent is a warning sign; above 0.3 percent triggers account review.
- Engagement rate. Mailbox providers increasingly weigh open and click rates as a deliverability signal. A list of inactive contacts pulls overall engagement down even when only the active subset is targeted, because the dormant addresses still receive enough messages to register as low-engagement.
Hygiene protects all three. It is cheap to maintain and expensive to skip.
Next
- The fair-usage operations doc for platform-level policy.
- The deliverability monitoring operations doc for the metrics you watch.
- Contacts for the underlying data model.