Block a person in Outlook by opening their message, clicking the block sender button, and confirming

The fastest way to block someone in Outlook is to open any message from that person, then click the block icon in the toolbar. Outlook will move all future messages from them to your Junk folder automatically. You do not need to delete the message first — blocking works on the sender's address, not the individual email.

If you use Outlook on the web (outlook.com or outlook.office.com), the block button appears in the top toolbar when you have a message open. If you use the Outlook desktop app on Windows or Mac, the button is in the same place. The exact wording varies slightly — it may say "Block" or "Block Sender" — but the result is the same.

Once you block someone, Outlook stops showing you their messages in your inbox. They go to Junk instead, and you can delete them without reading. The person does not receive a notification that you blocked them.

Key Takeaways

  • Open any message from the person you want to block, then click the block button in the toolbar to send all their future messages to Junk.
  • Blocking works the same way in Outlook on the web and the Outlook desktop app, though the button location may differ slightly.
  • Messages that arrive after you block someone go to Junk automatically, but messages already in your inbox stay where they are.
  • You can unblock a person later by going to your blocked senders list and removing their address.
  • Blocking is different from marking as spam — it prevents future messages from reaching your inbox, while spam reports help train Outlook's filters.

Where to find the block button in Outlook on the web

In Outlook on the web, open the message from the person you want to block. Look at the top of the message, where you see buttons for Reply, Delete, and other actions. Click the three dots (more options menu) if you do not see a block button when ready — the block option is usually there.

Once you click Block or Block Sender, Outlook asks you to confirm. Select "Block this sender" in the dialog box. From that moment on, any message from that person's email address goes straight to your Junk folder.

Where to find the block button in the Outlook desktop app

In the Outlook desktop app on Windows or Mac, open a message from the person you want to block. In the toolbar at the top of the message, look for a button labeled "Block" or "Junk" with a dropdown arrow. Click it and select "Block Sender" from the menu.

On some versions of Outlook, the button may be under the Home tab in the ribbon at the very top of the window. If you cannot find it in the message itself, click the Junk button in the Home tab and look for a Block Sender option there.

What happens to messages after you block someone

All new messages from a blocked sender go to your Junk folder. Outlook does not delete them — they sit in Junk until you delete them yourself or until Junk empties automatically (usually after 30 days, depending on your settings).

Messages from that person that arrived before you blocked them stay in your inbox or wherever they were. Blocking only affects future messages. If you want to remove old messages from someone, you can search for their address, select all their messages, and delete them manually.

How to unblock someone if you change your mind

To unblock a person, go to your Junk folder and find a message from them. Open it and click the "Unblock" button in the toolbar — it appears in the same place where the block button was. Confirm that you want to unblock them.

If you do not have any messages from that person in Junk, you can also manage your blocked senders list directly. In Outlook on the web, go to Settings (the gear icon), then View all Outlook settings, then Mail, then Junk email. You will see a list of blocked senders and can remove anyone from it. In the desktop app, go to File, then Options, then Trust Center, then Junk Email, and you will see the same list.

The difference between blocking and marking as spam

Blocking sends all future messages from someone to Junk. Marking a single message as spam does the same thing for that one message, but also tells Outlook's filters that similar messages are unwanted. Over time, marking messages as spam trains Outlook to catch similar emails from other senders.

If you block someone, you are saying "I do not want to see messages from this specific person." If you mark a message as spam, you are saying "This type of message is unwanted, and I want Outlook to learn to catch it." For a person you know but do not want to hear from, blocking is the right choice. For unsolicited bulk email or phishing attempts, marking as spam is more useful because it helps protect other people too.

Frequently Asked Questions

Will the person I blocked know that I blocked them?

No. Outlook does not send a notification to someone when you block them. Their messages straightforward go to your Junk folder instead of your inbox, and they have no way to know that happened unless you tell them.

Can I block someone if I do not have a message from them yet?

Not directly through the block button. You can only block someone by opening a message from them first. If you want to prevent someone from reaching you before they send anything, you can create a rule in Outlook that automatically moves their messages to Junk, but that requires knowing their email address in advance.

What if someone uses a different email address to contact me after I block them?

Blocking works on the specific email address you blocked, not the person. If they send you a message from a different address, it will reach your inbox normally. You would need to block that address separately. If someone is harassing you from multiple addresses, contact your email provider or your IT department for additional options.

Does blocking someone in Outlook also block them on other Microsoft services?

No. Blocking in Outlook only affects your Outlook inbox. It does not block them from contacting you through Teams, Skype, or other Microsoft services. You would need to block them separately in each service if you want to prevent contact everywhere.

Can I block an entire domain instead of just one person?

Not through the block button. You can only block individual email addresses. If you want to block all messages from a domain (like blocking everyone with an @example.com address), you need to create a mail rule in Outlook. In the desktop app, go to Home, then Rules, then Manage Rules and Alerts. In Outlook on the web, go to Settings and create a rule that moves messages from that domain to Junk.