Everything you need to check, understand, and remove your IP from the 0spam blacklist, including the network block list and what 0spam's own removal criteria actually require.
Quick answer: 0spam maintains a few separate zones, and which one you're on determines your options. The main list, bl.0spam.org, accepts a free manual removal request once the underlying spam source is fixed. The network block list, nbl.0spam.org, has no manual removal at all, if you're only listed there, you have to get your IP provider involved.
What is the 0spam blacklist, and which zone are you actually on
0spam isn't a single list. It's a small set of related zones, and mixing them up wastes time on the wrong fix.
bl.0spam.org is the main list. This is where an individual IP lands after 0spam observes spam coming from it directly. This is the one you can request removal from yourself.
nbl.0spam.org is the network block list. This lists an entire Class C block, not a single IP, once enough abuse has come from within that range. 0spam's own site states plainly that manual removal isn't available here. If you're listed only on nbl, the fix runs through your IP provider, not through you directly.
dbl.0spam.org and url.0spam.org cover domains and URLs found inside spam messages, rather than sending IPs. If a link in a spam email points to your domain, even if you never sent the mail yourself, that domain can end up here.
A separate, related realtime zone also exists alongside these for automated checks, which tends to clear on its own once the spam activity stops, without a manual request path either.
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0spam's own guidance points to a specific, practical set of causes, worth checking in this order.
An infected or compromised server. If malware or a compromised account is sending spam from your machine without your knowledge, this is often the actual root cause behind a listing that otherwise makes no sense.
Purchased or unverified mailing lists. 0spam specifically calls out list hygiene. If you're running a newsletter or mailing service, sending to a list that wasn't built through real double opt-in significantly raises your odds of hitting one of their spam traps.
Uncapped free email services. If you provide free email access to unverified users, 0spam's own guidance suggests capping outbound volume, around 200 messages a day per user, specifically to reduce abuse and listing risk.
An open relay or misconfigured DNS. A mail server that's improperly configured to let outside senders route through it, or DNS records that aren't set up correctly, are both flagged as common causes worth ruling out.
How to remove your IP, step by step
This follows what 0spam's own removal request actually asks for, not a generic template.
Step 1: Confirm which zone you're actually on. Since bl, nbl, dbl, and url each need a different response, check your exact listing before doing anything else.
Step 2: Scan for compromise first. Before requesting anything, scan your server for malware and confirm nothing is sending mail without your knowledge.
Step 3: Rule out being an open relay. Verify your mail server isn't configured to let unauthorized senders route through it, and confirm your DNS records are set up correctly. If you're not sure how, this is a point where getting an IT contact involved is worth it.
Step 4: Cross-check other blacklists. 0spam's own guidance recommends checking your IP against other blacklists too, using a tool like MXToolbox, before submitting your request, since a listing here often isn't the only one if the underlying cause hasn't been addressed.
Step 5: Submit a Removal request with a real explanation. 0spam's form specifically requires an explanation of what's been done to prevent future spam reports from your IP or range. A request that just says "please remove me" without naming the actual fix is weak. Be specific about what was wrong and what changed.
Step 6: If you're only on nbl, contact your IP provider instead. Manual removal isn't available for the network block list. Your provider needs to investigate and resolve it on their end.
How long does 0spam delisting take
0spam is a smaller, independent operation compared to something like Spamhaus, and it doesn't offer a paid fast lane, there's no way to speed this up beyond submitting an accurate, complete request. For the main bl list, requests are generally processed quickly once submitted correctly, though manual review can take longer in some cases. The network block list depends entirely on your provider's own process and the range staying clean afterward, so it's inherently slower and less predictable.
What to do after you're delisted
Getting removed from 0spam's list doesn't automatically restore your sender reputation. While you were listed, mailbox providers were quietly accumulating their own negative signals, bounces, spam folder placements, and reduced engagement, and those don't disappear the moment the listing clears. If your deliverability doesn't recover within a week or two on its own, treat it as a reputation rebuild, not just a delisting: keep volume modest, focus on recipients who actually engage with your mail, and keep authentication clean while trust rebuilds.
Frequently Asked Questions
What's the difference between bl.0spam.org and nbl.0spam.org?
bl.0spam.org lists individual IPs based on direct spam activity, and you can request manual removal yourself. nbl.0spam.org lists an entire network block, and manual removal isn't available, your IP provider has to resolve it.
Is 0spam delisting free?
Yes. 0spam is a donation-supported project, and removal requests for the main list are free. There's no paid option to speed up the process.
Why is my domain listed on 0spam's dbl or url list if I didn't send spam?
These lists track domains and URLs found inside spam messages, not just sending IPs. If a spammer included a link to your domain in their message, your domain can end up listed even if you never sent anything yourself.
Can I get removed from the network block list myself?
No. 0spam's own guidance is explicit that manual removal from the network block list isn't possible. You need to involve your IP provider directly.
Will my deliverability recover as soon as I'm delisted?
Not always immediately. The listing itself is only part of the picture, mailbox providers may have accumulated their own separate reputation signals while you were listed, which can take some time to recover even after removal.
