LashBack UBL is a IP blocklist published at blacklist.lashback.com. When you're listed, mail servers that consult LashBack UBLwill block, defer, or spam-folder your messages — so fixing it matters for deliverability. Here's why it happened and exactly how to get off.
Why you got listed
LashBack UBL listings almost always trace back to one of these:
Mailing to addresses that previously unsubscribed (or were scraped from unsubscribe pages)
Most commonMailing to addresses that previously unsubscribed (or were scraped from unsubscribe pages). This is the most common trigger for a LashBack UBL listing — address it first.
Using a purchased or rented email list
CommonUsing a purchased or rented email list.
Not honouring unsubscribe requests promptly
Less commonNot honouring unsubscribe requests promptly.
How to get delisted
Delisting that lasts has two parts: fix the root cause, then request removal. Skip the first part and you'll be re-listed almost immediately.
- 1
Find and stop the source
Identify what triggered the listing — a compromised mailbox, a script or web form being abused, a poor-quality list, or a misconfigured mail server. Check your outbound logs for unusual volume and secure any account that looks compromised (rotate passwords, enable MFA, revoke stale API keys).
- 2
Fix the underlying issue
Stop mailing unsubscribed and purchased addresses, suppress them permanently, then use the LashBack lookup to request removal. Re-listing is immediate if the behaviour continues, so list hygiene is the real fix.
- 3
Confirm your authentication is solid
Make sure SPF, DKIM, and DMARC are all passing before you ask for removal — a clean authentication setup is part of demonstrating you're a legitimate sender. Run a free EmailHealth check to confirm.
- 4
Submit a removal request at blacklist.lashback.com
Go to
blacklist.lashback.com, look up your IP to confirm the listing and its stated reason, and use their removal/delisting form. Many listings here also expire on their own once the cause stops.
Stay off it for good
- Keep your list clean — remove hard bounces and never mail purchased or scraped addresses
- Authenticate every sending source with SPF, DKIM, and DMARC
- Monitor your domain so you catch a new listing within a day, not after customers complain
EmailHealth can monitor your domain daily and alert you the moment a blacklist listing (or any other deliverability change) appears.