It says delivered but the recipient didn't get it

A delivered event means the receiving mail server accepted the message and returned a 250 OK success code over SMTP. That is the furthest point we can observe: once the recipient's server takes the message, it may file it in the inbox, queue it for later, route it to spam, or even discard it — and what happens next (a forwarding rule, a filter, a quarantine) is entirely on their side and is not reported back to us. Any later event (open, click, unsubscribe) requires the recipient to actually engage.

Where a "delivered" email usually is

Spam or quarantine

The most common landing spot. The server accepted the message (so it counts as delivered) and then filed it in the Spam/Junk folder, or held it in an admin quarantine that the user never sees. Ask the recipient to check Spam/Junk, and — on corporate accounts — to ask their admin to check the quarantine and release/allowlist your sender.

Aliases and forwarding

If the address is an alias or forwarder (e.g. team@ redirecting to several mailboxes, or a personal address forwarding to another provider), delivery to the first hop succeeds, but the forward to the final mailbox can be silently filtered or broken by SPF/DKIM alignment loss on the second hop. Confirm the real destination mailbox and test sending to it directly.

Provider-side filtering rules

User-created mail rules (filters that auto-archive, delete, or move messages by sender/subject) and organization-wide policies can move an accepted message out of the inbox immediately. Have the recipient search all folders (including Archive, Trash, and any custom folders) for your subject or from-address.

How to diagnose

1. 1
   Check the email log

   Open the email by its id in the dashboard (or via retrieve email). A delivered event with no bounce or complaint confirms the destination server accepted it.

2. 2
   Have the recipient search everywhere

   Spam/Junk, Archive, Trash, and custom folders — search by your from-address, not just the subject.

3. 3
   Check aliases/forwarding

   If the address forwards elsewhere, send a direct test to the final mailbox to isolate the second hop.

4. 4
   Ask about quarantine

   On business email, the admin quarantine is invisible to the user. Have them ask IT to check it and allowlist your domain.

If you can reach the recipient

The fastest fix is to have the recipient look in the likely hiding spots and, if they find your message, mark it Not Spam or add your domain to their allowlist:

• Corporate spam filters or firewalls
• Personal inbox filtering rules
• Promotional, spam/junk, or deleted folders
• Group inboxes or shared queues

Improve your odds next time

When you can't reach the recipient, you can still raise the chance the next message lands in the inbox:

• Publish DMARC to build trust with the receiving provider — see DNS records.
• Warm up new domains slowly before sending large volumes — see the warm-up guide.
• Align link domains with your sending domain (avoid shorteners and unrelated link hosts).
• Turn off open/click tracking for streams where placement matters most — tracking can read as promotional.
• Reduce images and trim the body; succinct, balanced HTML scores better than heavy marketing layouts.