How to Block a Domain in Outlook Mail on the Web

Block domains using blocked senders or email rules

Outlook Mail on the web makes it easy to block messages by individual senders from showing up in your inbox folder. For even more effective spam blocking, ban entire domains as well.

Instructions in this article apply to Outlook.com and Outlook Online.

Block a Domain in Outlook Mail on the Web

To have Outlook Mail on the web reject messages from all email addresses at a specific domain:

  1. Select Settings (the gear icon ⚙️).

    Screenshot of selecting gear icon in Outlook online
  2. Select View all Outlook settings.

    Screenshot of View all Outlook settings
  3. Select Mail > Junk email.

  4. In the Blocked senders and domains section, select Add.

    Screenshot of the Blocked senders and domains list
  5. Type the domain name you want to block, then press Enter to add the domain to the list.

    The domain name appears after the @ in an email address. For example, if the recipient is client1@clientcompany.com, the domain is clientcompany.com.

    Screenshot of adding a domain in blocked senders and domains
  6. Select Save, then close the Settings dialog box.

  7. When you get an email from that domain, it's automatically diverted to the Junk Email folder.

Block a Domain in Outlook Mail on the Web Using Filters

To set up a rule that automatically deletes certain emails — such as all emails from a domain you cannot block using the blocked senders list — in Outlook Mail on the web:

  1. Select Settings.

    Screenshot of the settings icon in Outlook online
  2. Select View all Outlook settings.

    Screenshot of View all Outlook settings
  3. Select Mail > Rules.

  4. Select Add new rule.

    Screenshot of Add new rule in Outlook online
  5. Name the rule, then select the Add a condition dropdown arrow and choose Sender address includes.

    Screenshot of Sender address includes in Outlook online
  6. In the Enter all or part of an address text box, enter the domain you want to block.

    Screenshot of typing domain name to block in Outlook online
  7. Select the Add an action dropdown arrow and choose Mark as Junk.

    Screenshot of Mark as junk in Outlook online
  8. Optionally, to specify conditions that prevent an email from being deleted even though it is from a blocked domain (or sender), select Add an exception, then choose From.

    Screenshot of allowing certain emails in a spam block rule
  9. Enter the email address you want to allow.

    Screenshot of excluding an email from a domain spam block
  10. Select Save to finish.

  11. Close the Settings dialog box.

Any email from the domain you've defined in the rule automatically goes to the Junk Email folder. Only email addresses you've specified in the exclusions are allowed in your inbox and won't be diverted to the Junk Email folder.