You were listed because an operator or an algorithm collected evidence that you represent a risk as a sender, whether it’s a spam risk or concerns of malicious activity.
The listing is one of the final stages of a reputation issue. The evidence is almost always one of three things.
A list you didn’t clean or manage properly — SPF, DKIM, DMARC
Too many complaints about your mailing program reported as “spammy”
Abuse you never sent: a compromised account or your domain being spoofed
Use cases · Domain or IP blacklisted
Domain or IP blacklisted
Why is my domain or IP blacklisted?
You were listed because an operator or an algorithm collected evidence that you represent a risk as a sender, whether it’s a spam risk or concerns of malicious activity.
The listing is one of the final stages of a reputation issue. The evidence is almost always one of three things.
A list you didn’t clean or manage properly — SPF, DKIM, DMARC
Too many complaints about your mailing program reported as “spammy”
Abuse you never sent: a compromised account or your domain being spoofed
01 – Are you actually blacklisted?
02 – What’s keeping you listed
03 – Major blacklist vs minor list vs provider block
04 – How MailSoar gets you delisted
05 – Email Deliverability Consulting Services
06 – Client results and testimonials
07 – Blacklisting FAQ
You’re on a blacklist. Your mail isn’t being filtered
For affected providers, every message bounces before it reaches a single inbox: campaigns, invoices, password resets, order confirmations. Every day your domain or IPs are listed, the underlying damage to your reputation deepens. In short, the longer you wait, the more difficult it will be to reach the inbox again.
Read the bounce
A hard bounce naming an operator (550 or 554) means a listing. No bounce, a ~99% delivery rate, and collapsing opens mean reputation damage, not a listing.
Check three things, not one
Your sending domain, every sending IP, and your click-tracking and link domains within a blacklist monitoring tool. Senders routinely delist their IP addresses and remain blocked because the listing is actually on their tracking domain.
Time to recover
Days to weeks for the removal itself, then 2 to 6 weeks to rebuild the underlying reputation, and that window grows by 1 week for every week you stay listed.
You got a blacklist warning
Bounce naming Spamhaus, Barracuda
A listing isn’t typically definitive
Usually, a listing becomes visible when your reputation with mailbox providers has been quietly degrading for months due to complaints, spam traps, bounces, and spam-like behavior.
01
Spam traps in your list
Recycled and pristine traps are the strongest trigger; one hit can list you. Purchased, scraped, aged, or inherited lists are the fastest route to them.
02
Spam complaints above threshold
The heaviest negative signal there is compounds daily until the source is identified.
03
No list hygiene or sunset policy
Bounces to dead addresses and dormant contacts tell providers nobody wants your mail.
04
Broken or misaligned authentication
Without aligned SPF, DKIM, and DMARC, operators can’t separate your mail from mail forged in your name.
05
Volume spikes without warm-up
A jump with no sending history matches the snowshoe pattern that operators actively hunt.
06
Shared IP with bad neighbors
Another sender’s abuse gets your mail rejected, too, and you can’t fix their behavior.
07
Listed link or tracking domain
A shortener or click-tracking domain on a DBL taints every message you send, regardless of your own domain deliverability scores.
08
Compromised account, unprotected form, or spoofed domain
Abuse sent through, or in the name of, your infrastructure lands on you and never appears in your ESP.
Not all blacklists are equal
Some are prominent and will lead to bounces and messages being rejected almost immediately, while others are more minor and will not affect you. Truthfully, some blacklists are outright frauds – listing entire IP ranges or newly purchased domains, for no real reason. The one you should care about will usually lead to bounce-back emails, deliverability issues, or even URL access troubles.
Recognize one of these problems? We solve them every day
Our senior consultants have fixed exactly these issues for 500+ brands. Book a free 30-min call and get your action plan.
A MailSoar expert finds the real cause and reverses it
You don’t need to negotiate with blacklist operators yourself, and trying to guess which of the eight causes above applies to you can be difficult and waste more time. Every minute wasted sends more negative signals to blacklists and mailbox providers, making recovery longer, harder, and far more expensive.
We confirm every listing across your domains, IPs, and linked domains, review your reputation and complaint data, and trace the root cause.
2
Fix the right thing
We close the cause before requesting a single removal so the delisting holds instead of restarting the cycle.
3
Back in the inbox
Rejections stop, and placement rebuilds typically occur within 2 to 6 weeks, depending on how long you were listed.
4
Stay off the lists
Monitoring across your domains, IPs, and link domains, plus implementing a data-driven sending discipline that stops operators from ever collecting evidence on you again.
A MailSoar expert finds the real cause and reverses it
You don’t need to negotiate with blacklist operators yourself, and trying to guess which of the eight causes above applies to you can be difficult and waste more time. Every minute wasted sends more negative signals to blacklists and mailbox providers, making recovery longer, harder, and far more expensive.
1
Diagnose
We confirm every listing across your domains, IPs, and linked domains, review your reputation and complaint data, and trace the root cause.
2
Fix the right thing
We close the cause before requesting a single removal so the delisting holds instead of restarting the cycle.
3
Back in the inbox
Rejections stop, and placement rebuilds typically occur within 2 to 6 weeks, depending on how long you were listed.
4
Stay off the lists
Monitoring across your domains, IPs, and link domains, plus implementing a data-driven sending discipline that stops operators from ever collecting evidence on you again.
When your IP or domain is blacklisted, most clients start by diagnosing and fixing the root cause. Explore our complete deliverability consulting offer below.
Find out if your domain or IP is on a blacklist, identify the root cause, and get expert guidance to get delisted and restore your sender reputation. Book a free call to solve the issue fast.
“MailSoar audited our email deliverability and provided recommended next steps. The audit was extremely thorough, and recommended next steps well communicated with a clear perspective on prioritization.”
Agicap
Finance
60%→98%
Inbox Placement
“MailSoar helped us stop the bleeding quickly, then restructure our email marketing, sales, and product approach. Problem solved!”
“Pierre and his team from Mailsoar have helped our company improve our email deliverability metrics to ensure that we get as many of our emails in our customers inbox as possible. Prior to his team working with us we saw a large number of emails going into spam, junk, or for the case of gmail, promotions/social. . As an online marketplace, emails are a crucial component to our supply and demand components interacting efficiently. This has helped improve that efficiency.”
“MailSoar had a huge impact on our business and I highly recommend them. They helped us grow our open rate from ~10% to almost 50% for our eCommerce store by optimizing our email strategy and implementing various deliverability tactics. We have been using their service for a few months now, and I couldn't be happier with their knowledge, expertise, and great communication.”
“We came to MailSoar to help with our deliverability. We were so happy with their work on this, that we have continued to work with them for the past year to monitor our deliverability and to act as trusted consultants for a very important email marketing program. Our email deliverability metrics have drastically improved since starting with MailSoar. As a result of this email performance and revenue improved drastically.”
“We partnered with MailSoar to improve our email deliverability and sender reputation. They helped us set up a new dedicated subdomain to isolate our transactional/marketing mail flow from our primary domain, and worked with us to bring our DMARC compliance up to 97%. Since implementing MailSoar's recommendations, our email delivery rate has climbed to 99.6%. Just as importantly, the sender reputation for both humanx.co and mail.humanx.co went from "Bad" to "High". A great turnaround that's had a real impact on our ability to reliably reach our audience.”
“From time to time, we have had issues with our deliverability, and every time MailSoar has helped us resolve the problem and put in practices that have kept us out of trouble. We went from a place of having consistent issues with deliverability a couple of years ago to a place now where we rarely have them. And even when we do, these guys are the absolute experts in what is going on in the industry and know how to get deliverability issues resolved instantly. Cannot recommend them highly enough.”
“We are facing email deliverability issues, and Mailsoar gave us great free advice to start, and then we went forward with an email audit from them that set us up to fix the issues we have.
In just over a week, we received an audit and an action plan that we are implementing to recover our email deliverability.
We are highly confident that the plan will work and be successful.”
“I was running a complex, large-scale email campaign (...) and unfortunately, we discovered that poor hygiene and other technical issues meant almost all of our emails were going to spam.
The MailSoar team was so proactive, creative, and professional. I knew I didn't just have a vendor: I had a true partner whom I could trust completely, and who cared about the success of this project as much as I did. MailSoar saved my email campaign contract. I absolutely could not have done this without them.”
“Pierre understood the expectations of the job, was able to properly articulate the challenges we faced, and did a great job communicating with us through every phase of the project until it was completed. Most importantly he successfully completed the project in a timely manner. I would highly recommend Pierre.”
“Adaptable, Excellent client service, Client-minded, Proactive, Performance, Availability, Analytical skills, Skillness, Very good relational skills, Good coaching, Helpful, Trustworthy, Punctual, Friendly, Quality of execution, Professional, Flexible, Responsive, Attentive, Good communication.”
Brevite
E-commerce
“A growth partner that really makes a difference.
MailSoar has had a major impact on our business by helping us seize new opportunities and streamline processes that were holding us back. Their expertise and support have made them a true growth partner, capable of delivering concrete results while supporting our development in a committed and sustainable manner.”
Naoris Protocol
SaaS
“Open rates above 40% and a rebuilt reputation
MailSoar provided us with decisive expertise by quickly assessing our situation, advising us, and executing an effective plan. In a short period of time, we achieved open rates above 40% and high click-through rates, while rebuilding our reputation score. Their intervention allowed us to escape the constant pressure surrounding campaigns and calmly refocus on content.”
Is your situation slightly different?
A listing often overlaps with these closely related problems.
Open & click rates dropping
ENGAGEMENT & OPEN RATES
Find out whether it’s your content, your list, or filtering — and fix the one that’s actually failing.
Start with your bounce messages — a real listing names the operator and usually includes a lookup URL. Then check your sending domain, every sending IP, and your click-tracking and link domains separately, because a listing on any one of them stops delivery. Multi-blacklist tools give a fast overview, but they can’t tell you which listings actually affect your delivery and which are noise.
Which blacklists actually matter?
Spamhaus is the one most mailbox providers and filters consult, so an SBL, CSS or DBL listing has an immediate, measurable impact. Barracuda, SpamCop, and Proofpoint/Cloudmark matter for specific provider populations. Others — UCEPROTECT’s level 2 and 3, among them — list entire IP ranges by default and are used by almost nobody. Knowing which is important is the difference between an urgent fix and a distraction.
I’m blocked at Gmail or Microsoft but not on any public blacklist. Why?
Because the major providers run their own internal reputation systems and don’t publish them. A Microsoft S3150 or Gmail 550-5.7.1 is a provider-level block based on their own signals, not a public listing — there’s no lookup to check and no removal form to file. It’s resolved by changing sending behavior, which means identifying what that behavior is.
Why did I get relisted right after being delisted??
Delisting without fixing the underlying issues only treats the symptom, not the cause. Leave a trap address on your list, and it will fire again on your next send. Operators track removal requests and respond harder to repeat offenders — replacing easy self-service removal with prolonged holds, manual reviews, and more difficult remediation work ahead. And many will only give a handful of attempts before they stop accepting your delisting requests. This is the strongest argument for diagnosing before requesting removal.
Will changing ESP or the domain fix this??
Rarely, and it often makes things worse. Domain reputation travels with your domain, so a migration carries the problem into the new stack while adding an unknown-IP warm-up on top. A fresh domain abandons whatever history you had and presents providers with an unknown sender suddenly sending volume — itself a spam signal. In most cases, the listing was caused by the sender’s behavior, not the platforms.
How MailSoar helps
MailSoar helps blacklisted senders by identifying which lists (Spamhaus, SURBL and others) flag their domain or IP and why, handling the delisting requests and fixing what caused the listing so it does not happen again. Arcads was delisted from SURBL and Spamhaus and went from 15% to 100% deliverability.
MailSoar at a glance
MailSoar is an international email deliverability consultancy specializing in inbox placement, sender reputation, email authentication and email infrastructure.
