Not all email addresses are simply “valid” or “invalid.” Some fall into a borderline category that requires careful handling. Mailerio uses a risk scoring system to help you make informed decisions and protect your sender reputation.
What “Risky” Means
An email is marked as risky when one or more of the following conditions are detected:
| Condition | Description |
|---|---|
| Catch-All Domain | The domain accepts all emails, even invalid ones. These addresses may appear deliverable, but can bounce later. |
| Mailbox Full / Temporary Issues | The recipient’s inbox may be full or temporarily unavailable, causing potential soft bounces. |
| Greylisted / Temporary Rejection | The mail server temporarily rejected the verification request. The address may still be valid. |
| Role-Based Address | Generic addresses (info@, sales@) that may not belong to a single individual. |
| Unusual Patterns | Syntax or provider irregularities that increase uncertainty. |
“Risky” does not mean undeliverable it means the likelihood of a bounce or engagement issue is higher than normal.
Risk Score System
Each email receives a numeric score (typically 0–100) representing deliverability confidence:
| Score Range | Risk Level | Recommended Action |
|---|---|---|
| 80–100 | Low Risk | ✅ Safe to send with normal campaigns. |
| 60–79 | Moderate Risk | ⚠️ Send with caution or to secondary campaigns. |
| 40–59 | High Risk | ❌ Avoid in primary campaigns; consider follow-up verification. |
| 0–39 | Very High / Undeliverable | 🚫 Do not send, high probability of hard bounce. |
Many businesses set thresholds (e.g., score ≥ 60) to automatically accept or reject emails in signup forms, CRM imports, or campaign lists.
Handling Risky Emails
1. Segmentation
- Place risky emails into a separate segment for monitoring.
- Consider sending low-priority campaigns or re-verification after a short delay.
2. Automated Rules
- Reject disposable, role-based, or low-score emails automatically.
- Allow catch-all addresses with a moderate score only if your system can handle potential bounces.
3. Re-verification
- Risky emails can change status over time. Recheck periodically before sending large campaigns.
- This is especially useful for temporary server issues or greylisted domains.
4. CRM / Signup Integration
- Use Mailerio’s API to check risk in real time during user signup.
- Apply custom rules for your business:
- Reject disposable emails.
- Block free or role-based addresses if you only accept business emails.
- Allow borderline emails but flag them for follow-up campaigns.
Deliverability Insights
Understanding the deliverability landscape helps you prevent issues:
- Hard Bounces: Immediate rejection of invalid emails. High risk for sender reputation.
- Soft Bounces: Temporary failures (full mailbox, greylisting). Risky but not fatal — can retry.
- No-Reply Emails: Won’t accept replies, may reduce engagement metrics.
- Catch-All Domains: Hard to validate accurately; may appear valid even if the individual mailbox doesn’t exist.
By combining risk scores, status flags, and your business rules, you can maximize deliverability while minimizing bounces and protecting your reputation.