Bounces: Why a contact didn't get your email



What the different bounce categories mean and instructions for what to do about it

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Bounces: Why a contact didn't get your email

"Bounces" are contacts that didn't get the email that you sent to them. We collect the data that their Internet Service Provider (ISP) gives us and pass it on to you in your email reports. Depending on the type of bounce you got, you may be able to fix the email yourself, contact your customer or their ISP to get Constant Contact "whitelisted", or remove the contact from your list. 

Note: The "Recommended for removal" display shows you Non-existent, Undeliverable, and Suspended bounces. Try to correct any typos in the email address before removing.


Types of Bounces

These categories of bounces will tell you why your email isn't getting delivered:

  • Non-Existent - These bounces happen when the contact's Internet Service Provider (ISP) says that an email address doesn't exist. It's like the post office saying there's no one with that name in the building. Double-check these addresses for obvious typos, or get in touch with the contact and see if they have a new email address. If the address continues to bounce over time, remove it from your lists. 
  • Undeliverable - Undeliverable messages are like a busy signal. When we attempted to send the email, the ISP wasn't responding. We'll keep trying to deliver the email for up to 3 days. If there's no response after that, we label it a bounce. The ISP may fix things, but if email keeps bouncing may want to remove it from your lists and see if the contact has a different email address to use. 
  • Suspended - Sending email repeatedly to the same non-existent addresses can negatively impact deliverability. To help with this, addresses that consistently bounce as non-existent are placed on an internal hold to prevent us from sending to them again. Constant Contact will not attempt to send any emails to these "suspended" addresses. We recommend that you remove these addresses from your list.
  • Blocked - When an email is blocked, the ISP has decided not to deliver it, likely because it thought the email was spam. That could be because the ISP was concerned about something specific in the email or it rejects email from large senders. Use the Spam Check button before you send your next email to reduce the chances of it being blocked because of content issues. If you are still getting blocked bounces from a larger domain (Yahoo, Gmail, etc.) please contact us to get it resolved. If it's a smaller domain or ISP, here are some steps you can take next.
  • Mailbox Full - When an Inbox is too full to continue receiving new email messages, the ISP sends back a Mailbox Full message. Usually this happens when mailboxes aren't being checked often enough. You may want to get in touch with the contact and find a better email address and, if this email address keeps bouncing, remove it from your lists. 
  • Vacation/Auto-Reply - Vacation and Auto-replies are the exceptions to the bounce rule! When someone sets up an Auto-reply, a bounce message gets sent to us even though the email is actually delivered. That means you don't have to do anything. The message is just a way to let you know that the contact might not see your email for a while.
  • Other - Sometimes an ISP doesn't use a standard error message when they send back the bounce information - we categorize these bounces as Others. Get in touch with the contact to get a better email address and you should probably remove it from your lists if it keeps bouncing.


Ongoing List Maintenance

Keeping up with your bounces will go a long way toward keeping your list clean. Here's how to do it:

  • Keep an Eye on Consistent Bounces - It's easiest to track who isn't getting your emails on an on-going basis if you export the bounces from recent emails into a file.
  • Ask for Updates - Encourage contacts to update their profiles.
  • More suggestions for good list maintenance can be found here.


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