Mail silently disappears
Listed senders get filtered to spam or rejected outright, so quotes and invoices never reach the customer.
Free Email Tool
Blacklist Checker
Email blacklists (blocklists) are lists of IPs and domains that receivers distrust. Land on one and your invoices and quotes quietly stop arriving. This guide explains how listings happen and what they mean — and a specialist will check your status and rebuild your reputation, free.
Information:
Automated checker coming soon
What this tool checks
What a blacklist check looks at.
A blacklist check looks at whether your sending IP or domain appears on the blocklists receivers use to filter mail. These are the parts that matter.
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Your sending IP status
Whether the IP address your mail is sent from appears on the major reputation blocklists.
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Your domain status
Whether your domain (and the links you send) appears on domain-based blocklists like SURBL or URIBL.
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Which lists, and how serious
Not all lists carry equal weight — a listing on a widely used list like Spamhaus matters far more than an obscure one.
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The likely cause
A listing is a symptom — compromised account, misconfigured server, spammy content or a shared-IP neighbour.
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The path to delisting
Each list has its own removal process, and removal only sticks once the underlying cause is fixed.
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Your wider reputation
Beyond yes/no, your sender reputation trend is what really governs whether your mail reaches the inbox.
Why it matters
A blacklisting quietly costs you customers.
Blacklists feed straight into how receivers filter mail. A listing rarely announces itself — you just stop hearing back.
You find out too late
There is no alert — you usually discover a listing only when a deal goes cold or a customer says "I never got that."
It signals a deeper issue
A listing often means a compromised account or misconfiguration that needs fixing, not just a removal request.
Common problems
Why senders end up blacklisted.
Listings almost always trace back to one of these. A check finds the listing; fixing the cause is what keeps you off.
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A compromised mailbox
An attacker uses a hijacked account to send spam, and your domain or IP gets listed for it.
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Poor authentication or reputation
Missing SPF, DKIM or DMARC and a weak sending history make receivers more likely to distrust and list you.
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A noisy shared IP
On shared infrastructure, a bad neighbour's spam can drag your deliverability down with theirs.
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Delisting without a fix
Requesting removal but never addressing the cause means you are relisted within days — a frustrating loop.
Preview the checker
Check an IP or domain's blacklist status
This is a preview of the automated blacklist checker we are building. It does not run a live lookup or store anything you type.
Coming soon
Automated checking is on its way. A human audit is available now.
We are building instant, automated checkers as part of our Email Operations Center roadmap. Until then, a specialist will run this check by hand as part of a free Email Audit — and explain what it means for your business in plain English, with no jargon and no obligation.
- A real specialist reviews your setup — not an automated guess.
- Plain-English findings and the next step that actually matters.
- Free, with no obligation — we work alongside your existing IT.
Questions
Answers, in plain English.
What is an email blacklist?
An email blacklist (or blocklist) is a published list of IP addresses or domains that have been associated with spam or abuse. Receiving mail systems consult these lists to help decide whether to accept, filter or reject incoming mail.
How did I end up on a blacklist?
The most common causes are a compromised mailbox sending spam, weak authentication and reputation, or sharing infrastructure with a bad neighbour. A listing is a symptom — finding and fixing the cause is what stops it recurring.
How do I get removed from a blacklist?
Each list has its own delisting process. The key point is that removal only holds if the underlying problem is fixed first — otherwise you are relisted within days. We handle both the removal and the root cause.
Are all blacklists equally serious?
No. A listing on a widely used list such as Spamhaus has a real impact on deliverability, while many small or obscure lists are barely consulted. Part of a proper check is judging which listings actually matter for your mail.
Does this tool check blacklists live?
Not yet — the automated checker is in development. This page explains blacklists and what a listing means, and the form is a preview that does not run a live lookup. For results today, request a free manual audit.
My quotes have stopped arriving — is this why?
Possibly. A blacklisting is one common cause of mail silently failing, alongside authentication and DNS issues. Our Email Deliverability service diagnoses the exact reason and fixes it so your mail reaches the inbox again.