How to block someone in Outlook
To block someone in Outlook, open the email from that person, select the three dots (more actions) at the top right, and choose Block. On the web version, the option appears in the same menu. Once blocked, that person's emails go to your Junk folder automatically, and they cannot see your read receipts or free/busy information. You can unblock them the same way if you change your mind.
The block applies across Outlook on your computer, phone, and the web — it syncs automatically. Blocked senders cannot tell they are blocked, and their messages will not clutter your inbox, but they can still send mail to you (it just lands in Junk). If you want to prevent someone from contacting you entirely, blocking is the first step; if they use a different email address, you will need to block that one separately.
Key Takeaways
- Blocked emails move to your Junk folder automatically, but the sender does not know they are blocked.
- The block works across Outlook on desktop, web, and mobile — you only have to do it once.
- If someone contacts you from a different email address, you must block each address separately.
- You can unblock a sender at any time by going to Settings and finding them in your blocked senders list.
- Blocking does not delete old messages from that person; it only affects new mail going forward.
Blocking someone on Outlook desktop
On Outlook for Windows or Mac, open any email from the person you want to block. Click the three dots (more actions menu) in the top right corner of the email. A dropdown menu will appear with several options, including Block. Click it, and a confirmation message will appear asking if you are sure. Select Block again to confirm.
After you block someone, their future emails will go straight to your Junk folder. Any emails from them that are already in your inbox will stay there — blocking does not delete past messages. If you want to clean up old emails from that sender, you can delete them manually or move them to a folder.
Blocking someone on Outlook web
In Outlook on the web (outlook.com or outlook.office.com), open the email from the person you want to block. Click the three dots at the top of the email message. Select Block from the menu. A popup will confirm that you have blocked the sender.
The process is the same whether you use a personal Outlook.com account or a work account through Microsoft 365. Once blocked, that sender's messages will route to Junk automatically, and the block will sync to your Outlook app on your phone and desktop within a few minutes.
Blocking someone on Outlook mobile
On the Outlook mobile app (iOS or Android), open the email from the person you want to block. Tap the three dots at the top right of the message. Scroll down and tap Block. Confirm when prompted.
Mobile blocking works the same way as desktop and web — the sender's future emails go to Junk, and the block syncs across all your devices. If you are using a work email account, check with your organization first, as some workplace policies restrict blocking options.
Viewing and managing your blocked senders list
To see who you have blocked, go to Settings in Outlook. On desktop, click the gear icon and select View all Outlook settings. On the web, click the gear icon and choose Settings. Look for Mail in the left sidebar, then select Junk email.
Under the Blocked senders tab, you will see a list of everyone you have blocked. To unblock someone, find their name or email address and click the trash or remove icon next to it. They will be unblocked immediately, and their emails will no longer go to Junk (though they may still be caught by other spam filters).
On mobile, go to Settings, tap Mail, then Junk Email. You should see your blocked senders list there, with the option to remove anyone from it.
What happens when you block someone
When you block a sender in Outlook, their emails arrive in your Junk folder instead of your inbox. They do not receive a notification that they are blocked — from their perspective, they are just sending mail normally. They cannot see whether you have read their messages, and they cannot view your free/busy calendar information if you use Outlook for scheduling.
Blocking is not the same as deleting or reporting spam. It is a personal filter that affects only your account. If the person is harassing you, you may also want to report their messages as phishing or junk to help protect other Outlook users, though this is optional.
When blocking is not enough
If someone continues to contact you from different email addresses after you block them, you will need to block each address separately. There is no way to block an entire domain or all addresses from one person at once in Outlook.
If the contact is threatening, abusive, or part of a pattern of harassment, consider reporting the messages to Microsoft and to your email provider's abuse team. You can also forward the messages to your IT department if it is a work account. In serious cases, you may want to involve local authorities or your email provider's support team.
Frequently Asked Questions
Can someone tell if I have blocked them?
No. When you block someone, they do not receive any notification. Their emails simply go to your Junk folder, and they have no way of knowing you blocked them unless you tell them directly.
Will blocking delete old emails from that person?
No. Blocking only affects new emails going forward. Any messages from that sender that are already in your inbox will remain there. You can delete them manually if you want to remove them.
What if someone contacts me from a different email address?
You will need to block each email address separately. Outlook does not have a feature to block all addresses from one person. If someone is using multiple addresses to contact you, block each one as it appears, or consider changing your email address if the harassment is severe.
Can I unblock someone after blocking them?
Yes. Go to Settings, find Junk Email, and look at your Blocked Senders list. Click the remove or trash icon next to the person's name. They will be unblocked immediately, and their future emails will go to your inbox again.
Does blocking work on my phone if I blocked them on my computer?
Yes. Outlook syncs your blocked senders list across all devices — desktop, web, and mobile. You only need to block someone once, and the block will apply everywhere you use Outlook.