Why IPs typically get listed
The most common cause is a broken or delayed unsubscribe process on the sending side.
If your list management tool doesn't sync suppressions fast enough, you can keep emailing someone who already opted out.
Shared IP pools are another common cause. If you send from a shared IP, another sender's bad list hygiene can get your IP listed too.
Purchased or rented email lists carry higher risk here, since consent and unsubscribe history are often unclear.
General list hygiene problems also apply, including old addresses that unsubscribed years ago but never got removed from active sending lists.
How to check if you're listed
Query both zones directly with a DNS lookup tool, since a listing on one doesn't guarantee a listing on the other.
Check ubl.unsubscore.com first, since that's the current, actively maintained zone name.
Then check ubl.lashback.com separately to rule out a legacy-zone listing that the newer name might not reflect.
A returned A record on either zone means that IP is currently listed.
Manual dual lookups are easy to forget mid-incident, which is where automated monitoring helps.
Try our Blacklist Monitoring tool for free today.
How to get removed
Start by identifying which unsubscribe or suppression failure caused the listing.
Pull your recent send logs and cross-check them against your suppression list for gaps.
Fix the underlying issue first. Make sure your unsubscribe requests sync to every sending system you use, not just one.
If you send through shared IPs, contact your email service provider, since they may need to address the listing on their end.
Removal itself is typically requested through the operator's own site rather than by email.
Because ubl.unsubscore.com and ubl.lashback.com are two separate zone names for the same underlying list, a single removal request should typically cover both.
Confirm that by re-checking both zones after your request goes through, rather than assuming one lookup covers everything.
How long it typically takes
Processing time for UBL delisting requests varies and isn't something we can state as a fixed number here.
Removal from unsubscribe-based lists like this one is often faster than spam-trap-based lists, since the underlying data point is a single behavior rather than a reputation pattern.
Still, budget time for the operator to review your request rather than expecting instant removal.
Re-check both zones a day or two after submitting, and again after a week if nothing has changed.
FAQ
How do I do a lashback blacklist check?
Run a DNS lookup against both ubl.unsubscore.com and ubl.lashback.com using your IP address in reversed octet format, the standard method for querying any DNSBL zone. Check both zones, not just one, since they're maintained as separate lookups for the same list. A returned result on either means you're currently listed. Automated monitoring tools can run this check on a schedule so you don't have to do it manually every time.
How do I remove my IP from LashBack?
First confirm which zone flagged you, then fix the unsubscribe or suppression gap that caused the listing. Submit a removal request through the operator's site once the underlying issue is resolved. Because both zones reflect the same list, one request should typically clear both, but re-check afterward to confirm. Don't submit repeated requests without addressing the cause first, since the underlying behavior will likely trigger relisting.
What's the difference between ubl.unsubscore.com and ubl.lashback.com?
They're two zone names pointing to the same underlying Unsubscribe Blacklist data. Unsubscore is the operator's current branding and the zone name most actively promoted now. Ubl.lashback.com is the original name, kept active so mail filters that still query it don't lose coverage. Checking both is the safest approach until you've confirmed which one your mail filtering setup actually queries.
Can a shared IP get listed because of someone else's mistake?
Yes. If you send from shared infrastructure, another sender's failure to honor unsubscribes can get the whole IP listed. This is common with shared hosting mail relays or budget email service providers. If you suspect this is the cause, contact your provider directly, since they control the sending infrastructure. Moving to a dedicated IP with clean sending practices can prevent this going forward.
Will fixing my unsubscribe process prevent future listings?
It significantly reduces the risk, since the UBL specifically tracks post-unsubscribe sends rather than general spam signals. Make sure suppression lists sync across every platform and tool you use to send email. Delayed syncing is one of the most common causes of repeat listings on this particular list. Regular audits of your suppression process are worth doing even after you're delisted.
