Why monitor blacklists?
Email deliverability can degrade quietly. A single blocklist entry on a commonly referenced DNSBL can send legitimate messages to spam or cause them to bounce outright — especially for password resets, receipts, and support replies. For small teams, the first sign is usually customer frustration. Blacklist Monitoring removes the guesswork by checking key lists on a schedule and notifying the right people when action is needed.
What we check
- DNSBL lookups for your IPs and sending domains on widely referenced lists.
- Result detail including the list name and the value returned by the DNS query.
- Change tracking so you see when a listing first appeared and whether it’s cleared.
- Frequency by plan (e.g., daily/hourly checks) to balance freshness with cost.
We report whether a domain/IP appears on a list and surface the raw code where available. Specific remediation steps differ by provider; we link to the list’s info page when possible.
Issues you’ll catch early
- Shared hosting IPs listed due to another tenant’s activity.
- Forgotten test servers sending mail without SPF/DKIM/DMARC.
- Forwarders creating backscatter that triggers listings.
- Compromised web forms causing spam bursts overnight.
Pair with Email Authentication (SPF/DKIM/DMARC) and DNS Safety for a complete picture.
Signals at a glance
How we classify results and what to do next.
| State | Meaning | Typical cause | Next step |
|---|---|---|---|
| Not listed | No match on checked lists | Normal sending behaviour | No action |
| Listed (new) | Appeared on one or more lists since last check | Spam burst, misconfig, shared-IP collateral | Pause non-essential mail, review logs, follow delisting guidance |
| Listed (persisting) | Still present after prior alert | Root cause unresolved or long review queue | Escalate with provider; consider changing IP or routing |
| Cleared | Previously listed, now removed | Delisting approved or TTL expired | Resume normal sending; keep monitoring |
Reducing false positives
DNSBL operators vary in methodology and TTLs. Some lists include short-lived entries for suspicious behaviour that clear on their own. To avoid noise, you can limit which lists we treat as critical for paging, widen grace windows, or downgrade repeated alerts to chat/email during working hours using your policies.
- Selectable lists: include or exclude specific providers.
- Grace/hold-down timers: wait N checks before paging, still recording the event.
- Per-domain/IP routing: escalate differently for marketing mail vs. transactional mail.
Feature snapshot & plan availability
Core capabilities are available on paid plans; exact limits vary by tier.
Protect your domain reputation
Get ahead of blacklist surprises and keep critical email flowing.
Enable blacklist monitoring