The fastest way to block an email address in Outlook
Open the email from the sender you want to block. Click the three dots (more actions menu) at the top right of the message. Select Block from the dropdown. Outlook will move all future emails from that address to your Junk folder automatically.
On Outlook web (outlook.com or Outlook on the web), the steps are identical: open the message, click the three dots, and choose Block. The sender's future emails go straight to Junk without reaching your inbox.
Once you block someone, you can still see their emails if you go looking in your Junk folder — blocking does not delete old messages, only stops new ones from appearing in your inbox. If you want to unblock them later, you can do that from your Junk folder settings.
Key Takeaways
- Blocking an email address in Outlook takes three clicks: open the message, click the three-dot menu, and select Block.
- Blocked emails land in your Junk folder, not deleted, so you can review them if you change your mind.
- The same process works in Outlook desktop, Outlook on the web, and Outlook mobile apps.
- You can unblock a sender anytime by going to Settings > Mail > Junk email and removing them from your blocked list.
Blocking someone in Outlook desktop (Windows and Mac)
In Outlook for Windows or Mac, right-click the email from the sender you want to block. A context menu appears. Click Junk, then select Block Sender. Outlook adds that address to your blocked senders list when ready.
Alternatively, you can open the email and use the three-dot menu at the top. Click the dots, find Junk, and choose Block Sender. Both methods do the same thing — they route all future mail from that address to Junk.
If you block someone by mistake, go to File > Options > Trust Center > Trust Center Settings > Safe Senders & Blocked Senders > Blocked Senders. Find the address in the list, select it, and click Remove.
Blocking someone in Outlook on the web
Log into outlook.com or your organization's Outlook web portal. Open the email from the person you want to block. At the top of the message, click the three dots (more actions). Select Block from the menu.
Outlook on the web does not show a separate Junk submenu like the desktop version — the Block option appears directly in the three-dot menu. Once you click it, the sender is blocked and their future emails go to Junk.
To unblock someone in Outlook on the web, click the gear icon in the top right, then View all Outlook settings. Go to Mail > Junk email. Under Blocked senders, you will see a list of all blocked addresses. Click the X next to any name to unblock them.
Blocking someone in Outlook mobile apps
On the Outlook mobile app (iPhone, iPad, or Android), open the email from the sender you want to block. Tap the three dots at the top right of the message. Select Block Sender from the menu.
The mobile app works the same way as desktop and web — the sender's future emails go to Junk. You can unblock them later by going to Settings > Mail > Junk email and removing them from your blocked list, though the exact path varies slightly between iPhone and Android.
What happens when you block someone
When you block an email address, Outlook does three things: it stops showing new emails from that sender in your inbox, it sends their future messages to your Junk folder, and it keeps a record of the block in your settings so you can undo it if needed.
Blocking does not delete old emails from that sender — they stay in your inbox unless you manually delete them. Blocking also does not notify the sender that you have blocked them. They will not know their emails are going to Junk; they will only notice if they never get a reply.
If the same person sends you emails from multiple addresses, you have to block each address separately. Blocking someone@example.com does not block someone.else@example.com. This is why blocking works better for one-off unwanted emails than for determined harassment — if someone is serious about reaching you, they can create new email addresses.
When to block versus when to report as spam
Use Block when you know the sender personally or recognize the address, and you straightforward do not want to hear from them anymore. Blocking is quiet and reversible — the sender does not know, and you can change your mind.
Use Report as Spam (or Report Phishing if it looks like a scam) when you do not recognize the sender and suspect the email is unsolicited, malicious, or a phishing attempt. Reporting sends a copy of the email to Microsoft, which helps them improve their spam filters for everyone. To report an email, open it, click the three dots, and select Report > Spam or Phishing.
In practice, many people block first and report second. If an email looks suspicious, report it before you block it — that way Microsoft gets the information they need to catch similar emails in the future.
Blocking email addresses versus blocking domains
Outlook's built-in block feature blocks individual email addresses, not entire domains. If you block john@spamcompany.com, emails from jane@spamcompany.com will still reach your inbox.
If you are being flooded with emails from many addresses at the same domain, you have two options. First, you can block each address individually as they arrive — tedious but straightforward. Second, you can create a mail rule (in desktop Outlook) or a filter (in Outlook on the web) that catches all mail from that domain and sends it to Junk automatically.
To create a rule in Outlook desktop, go to File > Options > Mail > Rules & Alerts > New Rule. Choose explore rule on messages I receive, then set the condition to from people or distribution list and type the domain (for example, @spamcompany.com). Set the action to move to folder and choose Junk. In Outlook on the web, go to Settings > Mail > Rules and create a rule with similar conditions.
Frequently Asked Questions
Can a blocked sender tell that I blocked them?
No. Outlook does not send a notification to blocked senders. They will not know their emails are going to Junk unless they contact you through another channel and you tell them, or unless they notice you never reply to their messages.
If I block someone, will they still see emails I sent them in the past?
Yes. Blocking only affects future emails from them to you. Old emails you sent to them remain in their inbox. Blocking is one-way — it does not erase your message history or prevent them from reading what you already sent.
Can I block an entire email domain instead of just one address?
Outlook's Block button only blocks individual addresses. To block an entire domain, you need to create a mail rule (desktop) or filter (web) that catches all messages from that domain and sends them to Junk. This is more powerful but also more permanent, so use it only if you are certain you never want mail from that domain.
What is the difference between blocking and unsubscribing?
Unsubscribing removes you from a mailing list — the sender stops sending you emails because you asked them to. Blocking stops emails from reaching your inbox but does not tell the sender anything. Use unsubscribe for legitimate marketing emails and newsletters. Use block for unwanted personal emails or senders who ignore unsubscribe requests.
Can I block emails by subject line or keyword instead of by sender?
Not with the Block button. The Block feature only works on sender addresses. To filter by subject line or keyword, create a mail rule (desktop) or filter (web) that looks for those words and sends matching emails to Junk. This is more flexible but requires a few extra steps in your settings.