Where this lives. Sign in and open /blocklist in the app.
What it does
Blocklist is the suppression wall: addresses, whole domains, and permanent unsubscribes that no campaign is allowed to email. Every outbound send is checked against it before it goes out.
Before you start
- Viewing the wall needs the "manage_leads" permission.
- Removing an entry needs "manage_compliance." Adding one only needs "manage_leads."
- Unsubscribes are terminal. They are recorded only from a real unsubscribe action and can never be added or removed by hand.
Set it up, step by step
- Open Blocklist and click "Block addresses or domains."
- Paste any mix of addresses and domains, one per line, or separated by commas or spaces. Use
@company.comorcompany.comto block a whole company, including every subdomain. - Check the live preview under the text box. It shows how many addresses and domains it recognized and flags anything it could not parse.
- Choose a Reason (manual, dnc, competitor, customer, compliance, bounce, or complaint), optionally add a Note, then click "Add [count] to the wall."
- Use "Export CSV" in the header to download the current wall.
- To check whether one address is blocked, scroll to "Will we email this address?", type it in, and click Check. It runs the exact same check the send engine runs: address rules, domain rules, and unsubscribe history.
- Search and filter the list with the search box, the All / Addresses / Domains toggle, and the reason dropdown.
- To remove a non-terminal entry, click Remove on its row, then confirm by clicking "Confirm removal."
What you should see
- A hero strip with three counts: Blocked addresses (exact matches), Blocked domains (covers every subdomain), and Unsubscribes (terminal, never removable).
- A terminal, unsubscribed entry shows a lock icon and the word "terminal" instead of a Remove control.
- The check tool answers "blocked," with the reason such as a domain rule, an unsubscribed terminal record, or the entry's stated reason, or "clear, not on the wall."
Common problems
- A provider refusing your sender, a 5.7.x code, is not the same thing as suppression, and it never adds anyone to this wall. That is a verdict about your sending account or host, not about the recipient. It shows up instead on Deliverability under "Receivers refusing your senders," and the recipient stays fully contactable from a different sender.
- A hard bounce, meaning a genuinely dead address, is what actually lands someone here automatically. A soft or ambiguous bounce is deliberately not suppressed, so a valid address is never blocked on a shaky signal.
- Blank cells or a partial paste never erase existing suppression data. Adding an address or domain that is already blocked just leaves it as is.
- If Add is disabled or shows nothing to add, check the live preview for "unrecognized" entries. Text that is not a valid email or domain is never silently added.
Related
What is the difference between a bounce and a provider refusal?
A 5.1.1 rejection means the address does not exist and is about the recipient. A 5.7.x rejection is a verdict about the sender: the receiving system examined your domain, your address or your authentication and declined. They live in different worlds and must never be handled the same way.
Should a 5.7.x refusal suppress the recipient?
No, and this is the most common bookkeeping error in cold email. The recipient did nothing. Suppressing them quietly destroys a list while the real fault stays in place. Pause the sending domain instead, or hold sends to that provider from that domain, then investigate.
What bounce rate is too high?
Above about two percent of hard bounces reads to a provider as a bought or stale list, and it is the fastest way to lose a domain that has just finished three weeks of warm-up. Verify addresses before sending rather than after.
Read next
Common questions
What is the difference between a bounce and a provider refusal?
A 5.1.1 rejection means the address does not exist and is about the recipient. A 5.7.x rejection is a verdict about the sender: the receiving system examined your domain, your address or your authentication and declined. They live in different worlds and must never be handled the same way.
Should a 5.7.x refusal suppress the recipient?
No, and this is the most common bookkeeping error in cold email. The recipient did nothing. Suppressing them quietly destroys a list while the real fault stays in place. Pause the sending domain instead, or hold sends to that provider from that domain, then investigate.
What bounce rate is too high?
Above about two percent of hard bounces reads to a provider as a bought or stale list, and it is the fastest way to lose a domain that has just finished three weeks of warm-up. Verify addresses before sending rather than after.
Read next
Last updated September 19, 2026. Written by the team that operates the platform.