The fastest way to block someone in Outlook

Open the email from the person you want to block. Right-click on their name or email address at the top of the message, then select Block Sender from the menu. Outlook moves all future emails from that address into your Junk folder automatically.

If you have already deleted the email, you can block the address without opening a message. Go to your Junk folder, find any email from that sender, right-click their name, and choose Block Sender. The setting takes effect when ready for new incoming mail.

On the web version of Outlook (Outlook.com or Outlook on the Microsoft 365 web app), the process is similar: open an email from the sender, click the three dots menu at the top right, and select Block. The blocked sender's future emails go to Junk.

Key Takeaways

  • Right-click a sender's name in any email and select Block Sender to send their future messages to Junk automatically.
  • Blocking does not delete emails already in your inbox — only new messages from that address are affected.
  • You can block up to 1,024 email addresses in Outlook, though most people never reach that limit.
  • If you block someone by mistake, you can unblock them by going to Settings and finding the blocked senders list.
  • Blocked senders can still send you mail — Outlook just hides it from your inbox view.

What happens when you block an email address

When you block a sender, Outlook does not delete their emails or prevent them from sending to you. Instead, their messages skip your inbox and land in the Junk folder. You can still see them if you open Junk, but they will not show up in your main inbox or trigger notifications.

The block applies only to that specific email address. If someone sends you mail from a different address, Outlook treats it as a new sender. This matters if you are blocking someone who has multiple email accounts or if they use a work email and a personal email.

How to see your blocked senders list

In Outlook on your computer, go to File, then Options, then Trust Center, then Trust Center Settings. Click Blocked Senders on the left side. You will see every email address you have blocked.

In Outlook on the web, click the gear icon in the top right corner, then View all Outlook settings. Go to Mail, then Junk email. The Blocked senders tab shows your full list.

From this same screen, you can remove addresses from your blocked list. Select the address and click Remove or the trash icon. Once you unblock someone, their emails will return to your inbox instead of Junk.

Blocking versus other ways to manage unwanted mail

Blocking sends mail to Junk but does not delete it. If you want to delete emails from someone automatically without seeing them at all, you can set up a rule instead. Go to File > Options > Mail > Rules and Alerts, then create a rule that deletes messages from that sender.

Another option is to unsubscribe from mailing lists. Many legitimate emails include an Unsubscribe link at the bottom. Clicking it removes you from that sender's list, though it can take a few days to take effect. This works better for newsletters and marketing mail than for personal harassment.

If you are receiving threats, hate mail, or persistent harassment, blocking is a first step, but you may also want to report the sender to Outlook or save the emails as evidence. Outlook has a Report Phishing option for suspicious emails, and you can forward threatening messages to your IT department or local authorities if needed.

Blocking on mobile Outlook apps

On the Outlook mobile app for iPhone or Android, open an email from the sender you want to block. Tap the three dots menu at the top right, then select Block Sender. The app will confirm the block and move the email to Junk.

To see your blocked list on mobile, go to Settings (the gear icon), tap Accounts, select your email account, then look for Blocked Senders or Junk Email. The exact menu name varies depending on your phone and app version.

Common reasons blocking does not seem to work

If emails from a blocked sender still appear in your inbox, the most common reason is that they are sending from a different email address. Check the full sender address — it may look similar to the one you blocked but have a slight difference. Block the new address separately.

Another possibility is that the email arrived before you set up the block. Blocking only affects new incoming mail, not messages already in your inbox. You can manually move old emails to Junk or delete them yourself.

If you are using Outlook through your workplace, your IT department may have overridden your personal block settings. Some organizations manage blocked senders centrally. Contact your IT support to ask whether they can add an address to the company-wide block list.

Frequently Asked Questions

Can someone tell if I blocked them?

No. When you block someone, they do not receive a notification. Their emails still send successfully from their perspective — they just land in your Junk folder instead of your inbox. They have no way to know you blocked them unless you tell them.

What if I block someone by mistake?

Go to your blocked senders list (File > Options > Trust Center > Trust Center Settings > Blocked Senders on desktop, or Settings > Junk Email > Blocked Senders on the web). Find the address you want to unblock and click Remove. Their future emails will go back to your inbox.

Does blocking someone in Outlook block them everywhere?

No. Blocking in Outlook only affects your Outlook inbox. It does not block them on social media, messaging apps, or other email services. You would need to block them separately in each service.

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

Outlook does not have a built-in block domain feature, but you can create a rule to delete or move all emails from a domain. Go to File > Options > Mail > Rules and Alerts, create a new rule, and set it to match emails where the sender's address contains the domain name (for example, @spammerdomain.com).

What is the difference between blocking and marking as spam?

Blocking moves future emails from that sender to Junk. Marking as spam does something similar but also tells Outlook's spam filter that this sender is unwanted, which may help train the filter for similar addresses. For most users, blocking is simpler and works just as well.