Get Notifications When Your Messages Are Read in macOS Mail

By default, macOS Mail doesn't support read receipts—notifications that the recipient of your email has opened it; however, if you're comfortable working in Terminal, you can make the necessary modifications to start requesting read receipts from your email recipients.

Typically, Mail will ask the recipient to confirm they opened the email, after which you'll get a message to that effect. While this feature doesn't guarantee that the person actually read the email, it does confirm that it hit their Inbox, and you can rule out delivery failure.

Here's how to enable this feature:

1. Open Terminal from your Mac's Utilities folder.

   "Utilities" is inside the Applications folder.

   

2. At the prompt, type:

   defaults read com.apple.mail UserHeaders
   
   

   and press Return.

3. If that command returns an error that reads, "The domain/default pair of (com.apple.mail, UserHeaders) does not exist," type the following, replacing "Name" and "email address" with your own, and then press Return. For example:

   defaults write com.apple.mail UserHeaders '{"Disposition-Notification-To" = "Name <email address"; }'
   
   
   

4. You're done at this point unless the defaults read command above returns a line of values that starts with { and ends in }. If so, take the following steps to finish setting up read receipt requests.

   

5. Highlight the entire line. It might read something like {Bcc = "bcc@example.com"; }, for example.

6. Copy that highlighted line with the Command+C shortcut, but don't paste it yet. Instead, type this (but don't press Return yet):

   defaults write com.apple.mail UserHeaders 
   
   

7. Put a space at the end of the line, and then single quote, and then paste what you just copied so that it shows up after what was just typed. End it with a single quote.

8. Insert "Disposition-Notification-To" = "Name <email@address>"; ' in front of the closing } character, again replacing Name with your name and email@address with your email address.

9. Press Enter. The line might now read like this:

   defaults write com.apple.mail UserHeaders '{Bcc = "bcc@example.com"; "Disposition-Notification-To" = "John Doe <sender@example.com>"; }'
   
   
   

To Disable Automatic Read Receipt Requests

Turning off this setting is just as easy. As above, open Terminal again. Simply type the following, then hit Enter.

defaults delete com.apple.mail UserHeaders