Block a sender in Outlook on the web

Open the email from the sender you want to block. Click the three dots (more actions) in the top right of the message. Select Block from the menu. Outlook moves all future emails from that address to your Junk folder automatically.

You can also block a sender without opening their email. Right-click the message in your inbox list and choose Block. The sender is added to your blocked list when ready, and their past emails stay in your inbox unless you delete them manually.

To see all blocked senders, go to Settings (the gear icon), then Mail, then Junk email. Under "Blocked senders", you can view everyone you have blocked and remove anyone from the list if you change your mind.

Block a sender in Outlook desktop app

Right-click any email from the sender you want to block. Select Junk, then Block Sender. The address goes into your blocked list, and Outlook sends their future emails to the Junk folder.

You can also block someone from the message itself. Open the email, click Junk in the toolbar at the top, and choose Block Sender. The result is the same — future emails land in Junk.

To manage your blocked senders list in the desktop app, go to File, then Options, then Trust Center, then Trust Center Settings. Click Blocked Senders to see everyone you have blocked, add new addresses manually, or remove someone from the list.

Key Takeaways

  • Blocking a sender in Outlook sends their future emails to your Junk folder automatically, but does not delete emails they already sent you.
  • In Outlook on the web, use the three-dot menu or right-click to block; in the desktop app, use the Junk menu in the toolbar.
  • You can view and manage your blocked senders list in Settings (web) or Trust Center (desktop app) and unblock addresses anytime.
  • Blocking works on individual email addresses, so if a sender uses multiple addresses, you will need to block each one separately.

What happens when you block someone

When you block an email address, Outlook does not notify the sender. They will not know you have blocked them. Their emails still arrive at Microsoft's servers, but Outlook automatically sorts them into your Junk folder instead of your inbox.

If you block someone by mistake, you can unblock them anytime. Go to your blocked senders list, find the address, and remove it. Their future emails will return to your inbox, though emails that went to Junk while they were blocked stay there unless you move them back.

Block email addresses you have not received mail from yet

You do not have to wait for an email to arrive before blocking an address. In Outlook on the web, go to Settings, then Mail, then Junk email. Under "Blocked senders", type the email address you want to block and click Add.

In the desktop app, go to File, Options, Trust Center, Trust Center Settings, then Blocked Senders. Click Add, type the address, and click OK. That address is now blocked even though you have never received mail from them.

Difference between blocking and unsubscribing

Blocking and unsubscribing are not the same thing. When you block a sender, all their emails go to Junk. When you unsubscribe, you ask them to remove you from their mailing list — but they have to honor the request, and you are trusting they will.

For marketing emails and newsletters, unsubscribe is usually the right choice. Look for an "Unsubscribe" link at the bottom of the email. For unwanted or suspicious emails, blocking is faster and more reliable because it does not require the sender to do anything.

If you block someone, you will not see an unsubscribe option anymore because their emails go straight to Junk. If you want to unsubscribe first, do that before you block.

When blocking is not enough

Blocking works for unwanted emails from known addresses. If you are receiving many emails from different addresses that look similar or if the sender keeps creating new addresses to get around your block, that is a sign of a larger problem.

Report the email to Microsoft before you delete it. In Outlook on the web, click the three dots and select Report phishing or Report junk. In the desktop app, click Junk in the toolbar and choose Phishing or Junk. Microsoft uses these reports to improve spam filters for everyone.

If you believe your account has been compromised or if you are being harassed, change your password when ready and enable two-factor authentication on your Microsoft account. Those steps are more important than blocking individual addresses.

Frequently Asked Questions

Can I block an entire domain instead of just one email address?

Outlook does not have a built-in way to block all addresses from a domain at once. You have to block each address individually. If you are receiving many emails from the same domain, report them as phishing or junk so Microsoft can investigate the source.

Will the blocked sender know I blocked them?

No. Outlook does not send any notification to the sender. They will not receive a bounce-back email or any other signal that you have blocked them. Their emails straightforward disappear into your Junk folder.

Can I block someone on my phone?

Yes. In the Outlook mobile app, swipe left on the email (iPhone) or long-press it (Android), then tap the block or trash icon. The sender is added to your blocked list across all your devices.

What if I block someone and then want to read their old emails?

Blocking does not delete past emails. They stay in your inbox. Go to your inbox, find the emails from that sender, and read them normally. You can also move them to a folder if you want to keep them organized separately.

Do I need to block someone if I just delete their emails?

Deleting emails one at a time is slower than blocking. If you delete an email but do not block the sender, their next email arrives in your inbox and you have to delete it again. Blocking sends all future emails to Junk automatically, so you only have to act once.