Can You Block an Email Sender in Outlook? How It Works

Yes. Outlook lets you block an email address, and many versions also let you block an entire sending domain; messages from blocked senders are generally routed to Junk Email rather than erased. The exact steps depend on whether you use Outlook on the web, the new Outlook, classic Outlook for Windows, or Outlook for Mac.

What blocking a sender does

Blocking tells Outlook or the connected mail service to treat mail from a specified address as unwanted. In most Microsoft mailbox experiences, later messages from that address go to the Junk Email folder, where you can review them or delete them. Blocking is not the same as deleting an existing message: it does not automatically remove earlier mail from your Inbox or other folders.

A blocked address is usually a specific mailbox, such as newsletter@example.com. If the sender uses several addresses, blocking one may not stop mail from the others. A blocked domain, such as example.com, is broader: it can catch messages sent from many addresses ending in that domain. Domain blocking can also catch wanted mail, so use it only when you are confident that messages from the whole domain are unwanted.

Blocking is a filtering action, not a guarantee that a person can never contact you. Senders can use a different address, and unwanted messages can sometimes be misclassified or routed according to settings controlled by your email provider or workplace administrator.

Block a sender in Outlook on the web or new Outlook

The settings route is useful when you want to add an address even if you have already deleted its message. In Outlook on the web and the new Outlook for Windows, open Settings using the gear icon, then go to Mail > Junk email. Under Blocked senders and domains, choose the option to add a sender or domain, enter it, and save the change. Labels can vary slightly as Microsoft updates the interface.

You can also start from a message. Select or open the unwanted email and look in the message toolbar or its three-dot menu for a block option, such as Block or Block sender. The exact location can differ between Outlook on the web and the new Outlook, and may depend on the window size. If the option is not visible, use the settings route above.

Open Outlook and select the gear icon.
Choose Mail, then Junk email.
Find Blocked senders and domains and add the complete email address or domain.
Save the entry, then check the list to confirm it appears.

For example, adding offers@shop.example targets that address. Adding shop.example may affect messages from other addresses at that domain as well. Do not include a person’s display name in place of the actual email address; display names are easy to change and may not identify the sender reliably.

Block a sender in classic Outlook for Windows

In classic Outlook for Windows, select a message from the sender. On the Home tab, open Junk and choose Block Sender. Depending on the layout, you may also be able to right-click the message and choose Junk > Block Sender. Outlook may ask you to confirm the action.

To inspect or edit the list, use Home > Junk > Junk E-mail Options, then open the Blocked Senders tab. From there you can add or remove entries. If the Junk menu is missing, confirm that you are using classic Outlook rather than the new Outlook; the two Windows apps have different menus. In a work or school account, your organization may also limit which junk-mail controls are available.

After blocking, check the Junk Email folder rather than expecting the message to disappear. If the original message is still in the Inbox, blocking does not necessarily move that existing item for you. Move or delete it separately if you no longer want to keep it.

What to know about Outlook for Mac

Outlook for Mac has changed its menus across versions, so the most dependable route in a current interface is to open Outlook’s settings and look under Mail for Junk email or blocked-sender controls. If your version offers a block command on a message, select the message and check its toolbar or context menu. Menu names and locations can differ between the newer and legacy Mac interfaces.

If you cannot find a blocked-sender list in the Mac app, sign in to the mailbox through Outlook on the web and check Settings > Mail > Junk email. This can help distinguish an Outlook app menu issue from an account-level limitation. For a Microsoft 365 work account, the organization’s mail policies may determine which controls are available, regardless of whether you use a Mac or Windows computer.

Blocking an address versus blocking a domain

Choose the narrowest entry that solves the problem. Blocking an individual address is sensible when one sender is repeatedly contacting you but you still receive legitimate mail from the same company or institution. Blocking a whole domain is more appropriate when unwanted messages repeatedly arrive from different addresses at that domain and you do not need mail from any of them.

Block an address when the same mailbox is the source of unwanted messages.
Block a domain when multiple unwanted addresses share a domain and legitimate mail from that domain is not needed.
Do not block a familiar provider’s entire domain just because one message is suspicious; that could affect unrelated, wanted messages.

A domain entry is not a universal shield against a sender who changes domains or forges sender information. If a message appears to come from a trusted company but has suspicious links or requests, do not assume that blocking the displayed address will address the underlying risk.

If blocked emails keep arriving

First, compare the actual sender address on a new unwanted message with the address you blocked. The display name might be the same while the underlying address has changed. If the sender is using several addresses, you can add the new ones individually, but repeated changes may be a reason to report the messages as junk or phishing instead of maintaining a long list.

Next, check the Junk Email folder and the blocked-sender list. A message arriving in Junk may mean blocking is working even though Outlook has not deleted it. If it remains in the Inbox, verify that the entry was saved to the correct mailbox and that you are viewing the account where you made the change. Some people have multiple personal, work, or school accounts open in the same Outlook app.

Also consider whether the message is actually from a mailing list or a service you signed up for. Legitimate subscription messages may come from changing addresses, and blocking just one address may not stop the series. Use the service’s unsubscribe link when the message is genuine and you want to stop that subscription. For suspicious messages, avoid clicking links, opening attachments, or using an unsubscribe link that may be fraudulent.

For a work or school mailbox, contact your IT administrator if the setting is absent or does not behave as expected. Central mail-flow rules, security filtering, or organizational policy can affect delivery, and an individual Outlook block list may not override those controls.

Block, report, unsubscribe, or create a rule?

These options solve different problems. Blocking is useful for repeated unwanted mail from a particular address or domain. Reporting junk or phishing gives the mail service a signal about a message; phishing reporting is especially relevant when a message impersonates a bank, employer, or known company. The report command is not a substitute for protecting an account if you have already shared a password or payment details.

Unsubscribe is generally best for a legitimate newsletter or marketing list that you no longer want. A rule is useful when you want a custom action, such as moving messages with a particular subject to a folder or deleting mail that meets specified conditions. Rules can be broader than a sender block, so check the conditions carefully to avoid hiding important messages. You can combine actions when appropriate: report a deceptive message, then block the sender if it continues.

Safety and account considerations

Blocking does not make a suspicious email safe to open, and it does not remove malware or undo information you may already have disclosed. If an email claims to be urgent, asks for a password, requests a payment, or pressures you to open an attachment, verify the request through a separate trusted channel. Do not reply just to tell a suspicious sender to stop; replying can confirm that your address is active.

Keep in mind that the Outlook app is a way to access an email account, while some filtering decisions are made by the mail service behind that account. A Microsoft account, a Microsoft 365 work mailbox, and a third-party account configured in Outlook may not share identical settings or behavior. A block you add in one place might not appear in another account’s settings. When in doubt, check the account’s webmail settings and confirm which address is signed in.

Frequently Asked Questions

Does blocking someone in Outlook delete their old emails?
No. Blocking mainly affects how later messages are handled. Existing messages usually remain where they are, so move or delete them separately if you want them gone.

Will a blocked sender know that I blocked them?
Outlook generally does not send the blocked person a notification. Their messages may still appear to send successfully from their side, even if your mailbox routes them to Junk Email.

Can I block an entire email domain in Outlook?
In supported Outlook and Microsoft mailbox settings, you can add a domain to the blocked-senders list. This is broader than blocking one address and may also divert wanted messages from that domain.

Why is a blocked sender still in my Inbox?
Check that you blocked the actual address in the correct account, not just the display name, and confirm the entry was saved. The message may also have arrived before the block was added or come from a different address.

How do I unblock an email sender?
Open the blocked-senders list in the settings for the mailbox, find the address or domain, and remove it. In classic Outlook for Windows, use Home > Junk > Junk E-mail Options > Blocked Senders. After unblocking, future messages may be handled by other junk filters or rules.

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