Hi @Ming Tong
Thanks for reaching out to the Microsoft Q&A forum.
Based on my testing, in Outlook for Android, the To field does show the alias email address when you expand the email header. However, this requires an extra step and can be inconvenient. At the moment, Outlook on Android does not display the full email address without expanding the header after opening the email.
From my testing, here’s an approach you can consider to better manage your mailbox:
You can create an Outlook rule with the condition “Message header includes” and enter your alias in the value field. This rule can move messages to a dedicated folder for that alias or apply a category for easier organization.
To create an Outlook rule:
- Sign in to Outlook on the web from your computer.
- Open Settings by clicking the gear icon near your avatar.
- Navigate to Mail > Rules > Create a rule similar to the example shown in the image below.
- You can also choose Run rule now to apply it to existing messages.
If your alias represents a department or group, I highly recommend using a distribution list or Microsoft 365 group instead. This approach ensures messages show the specific email address while still allowing you to receive emails normally as a member of the group.
I hope this helps! If you have any updates or further questions, please feel free to share.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.