What is a suppression?
A suppression is a flag kept by our email provider (Postmark) that says: “don’t send to this address right now.” Suppressions exist to protect your team’s sending reputation. Email providers like Gmail and Outlook watch how your messages are received — if you keep sending to addresses that bounce or that report you as spam, your deliverability for everyone else suffers.
Rather than let that happen quietly, Jelly surfaces suppressions so you can see what’s happening and decide whether to act.
Why might an address be suppressed?
There are three main reasons an address ends up on the list.
Hard bounce
Our email provider tried to deliver a message and the receiving server permanently rejected it. The mailbox may not exist (typo, employee left, domain shut down) or it may be full. A hard bounce is different from a temporary failure; we only suppress after the provider is confident delivery won’t work.
Spam complaint
The recipient clicked “Report spam” on a message from you in their mail client. The receiving provider then tells our provider about it, and the address is added to the list. This is the suppression type to be most careful with — reactivating someone who reported you as spam and then emailing them again is a good way to damage your sender reputation.
Manual suppression
Added directly, either by someone on your team or by our email provider’s admin tools.
What does it mean when addresses show up?
A handful of suppressions over time is normal. Every team that sends enough email eventually hits a few dead mailboxes.
A sudden jump is usually worth investigating — it often points to a bad mailing list, an outdated contact import, or a reply going out to an address that shouldn’t be receiving customer mail (like a no-reply sender).
What can I do about them?
Open Email Setup in your team settings; if there are any suppressed addresses, you’ll see a Manage suppressed addresses button. From there you can:
- Search for a specific address, which is useful if a customer has told you they’re not getting your replies.
- Review the reason and when it was added, which is usually enough context to decide whether to act.
- Reactivate an address — this removes the suppression from our email provider so you can try sending to it again.
Reactivating isn’t a magic fix. If the underlying problem hasn’t been resolved — the mailbox is still full, the domain is still gone, the person still thinks your messages are spam — the address will end up suppressed again the next time you try to send.
Before reactivating a hard-bounced address, double-check it. A single typo in an address book can produce a bounce every time; fixing the typo at the source is more useful than reactivating the wrong address.
Spam complaints deserve a second thought. If a recipient explicitly reported you as spam, the safest thing is usually to respect that and not email them again unless they’ve asked to hear from you.
What about block lists?
Sometimes an address is suppressed not because you had trouble with it, but because it appears on an external block list — services like Spamhaus or SpamCop that track addresses (and the domains they belong to) reported as spam traps, known abusers, or part of compromised mail systems. Mail servers consult these lists when deciding whether to accept a message, and our email provider checks them too, so a listed address can end up on your suppression list even on its very first send attempt.
If a legitimate recipient has been caught up in one of these lists — maybe their own domain has a reputation problem unrelated to them — you can:
- Check their domain at a tool like mxtoolbox.com/blacklists.aspx to confirm which list they’re on.
- Ask the recipient to look into the listing with their own IT team or email provider; removal is the list operator’s process, not ours.
- Reactivate the address in Jelly in the meantime if you need to try sending again — just be aware that other mail servers along the way may still reject the message until the underlying listing is resolved.
Will Jelly warn me before I send to a suppressed address?
Yes. When you try to send a message where any recipient is on the suppression list, Jelly blocks the send and points you at the suppressed addresses page so you can either reactivate the address or remove it from the recipient list.