Send an Encrypted Email in Outlook

Send an Encrypted Email in Outlook

Send an Encrypted Email in Outlook

Overview

Encrypted email protects sensitive information so only the intended recipient can read it. Use encryption when sending things like account numbers, health information, contracts, or anything you would not want forwarded by accident. Microsoft 365 encryption works with anyone — they do not need to use Outlook to read it.

Before You Begin

  • Outlook for Windows, Mac, or the web, signed in with your work account.
  • The recipient's correct email address.
  • A clear sense of what you are protecting and why.

Steps

Outlook on the Web

  1. Open Outlook in your browser at outlook.office.com.
  2. Click New mail.
  3. In the message toolbar, click Encrypt. A banner appears confirming the message is protected.
  4. To restrict the message further, click Change permissions and choose Do Not Forward or another policy.
  5. Compose your message, attach files, and click Send.

Outlook for Windows or Mac

  1. Open Outlook and click New Email.
  2. On the Options tab in the ribbon, click Encrypt.
  3. Choose a permission level (for example, Encrypt-Only or Do Not Forward).
  4. Compose your message and click Send.

What the Recipient Sees

  • If the recipient uses Microsoft 365, the encrypted message opens normally in their inbox.
  • If they use Gmail, Yahoo, or another service, they receive a notification email. They click Read the message, then sign in with their email provider or request a one-time passcode.

Troubleshooting

  • If you do not see the Encrypt button: make sure Outlook is fully updated. Restart the app after updating.
  • If the recipient says they cannot open the message: confirm you sent to the correct address. Ask them to use the one-time passcode option instead of signing in.
  • If you need to send a very large attachment: share via OneDrive or SharePoint with link permissions instead of attaching the file directly.
  • If you are sending regulated data (HIPAA, financial, legal): check with your manager that encryption alone meets your company's policy. Some workflows require a secure portal instead.

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