How to add read receipt in mail app

To add a read receipt in the Mail app on your iPhone or iPad, follow these steps:

For iOS 10 and later:

1. Open the Mail app and go to the message you want to send with a read receipt.
2. Tap the "Compose" button to start a new message or reply to an existing one.
3. Tap the "Send" button to send the message.
4. Before sending the message, tap the "Send" button again to open the "Send Options" menu.
5. Toggle the "Send Read Receipt" switch to the "On" position.

For iOS 9 and earlier:

1. Open the Mail app and go to the message you want to send with a read receipt.
2. Tap the "Compose" button to start a new message or reply to an existing one.
3. Tap the "Send" button to send the message.
4. Before sending the message, tap the "Send" button again to open the "Send Options" menu.
5. Scroll down and toggle the "Request Read Receipt" switch to the "On" position.

Note: Read receipts are only available for messages sent to other Apple devices or devices that support read receipts. If you send a message to a non-Apple device, the read receipt feature will not work.

Also, keep in mind:

• The recipient's device must be configured to receive read receipts for the feature to work.
• Read receipts are not available for messages sent using the "Send as SMS" option.
• Read receipts are not available for messages sent to groups or distribution lists.