How To Flag An Email In Outlook

The sheer volume of messages most Outlook users receive every day makes it dangerously easy for important emails to go unnoticed until it's too late to reply without an apology. To combat this problem, you should learn how to flag emails in Outlook, and that's exactly what our guide will teach you.

Step-By-Step Guide on How to Flag an Email in Outlook

It doesn't take much effort to flag an email in Outlook, and we explain how to do just that using both the web version of Outlook and the desktop client.

💡 Note: Flagged emails are highlighted with a small flag icon across all versions of Outlook. By clicking the Flag / Unflag button, you not only add the flag icon to the message but also create a task in the Flagged email section of Microsoft To Do or Outlook Tasks (legacy version only).

Flag Emails in Outlook on the Web

Follow these steps:

  1. Log in to your mail account on the web.
  2. Select the message you want to be flagged.
  3. Click the Flag / Unflag button in the top toolbar.

Next to the Flag button, there is a small down arrow. You can click this arrow to reveal a dropdown menu with a list of items for flagging the selected message as a task with a specific start and due date.

💡 Tip: Alternatively, you can hover the mouse cursor over any message in your inbox to reveal and click the small flag icon located on the right.

Flag Email in Outlook Desktop

Flagging in the desktop version of Outlook is a matter of a few simple steps:

New desktop app version

  1. Launch the application on your computer.
  2. Select the message you want to be flagged.
  3. Click the Flag option in the top toolbar. To flag the selected message as a task with a specific start and due date, click the down arrow and then choose the desired date.

Legacy version

  1. Launch Outlook on your computer.
  2. Select the message you want to be flagged.
  3. Click the red flag icon in the toolbar. To mark a selected message as a task with a designated start and end date, click the down arrow next to the red flag icon and then choose the desired date.

💡 Note: Just like in the web version of the service, you can also quickly flag messages by hovering the cursor over their inbox previews and clicking the corresponding flag icons.

Regardless of which of the above-provided sets of instructions on how to flag emails in Outlook you decide to follow, only the selected message or messages will be marked. But what if you want to mark all future messages from the same sender or senders as well? Then you should use Clean Email, a third-party inbox organizer with many easy-to-use features that can instantly take your inbox management to the next level.

How to Automatically Flag Emails in Outlook Using Clean Email

We believe that Clean Email is superior to Outlook rules when it comes to automatically flagging all emails from specific senders because it makes it possible to achieve the desired results with a single flip of a toggle. Here's how:

  1. Go to
  2. Sign in with your Outlook account.
  3. Select the Senders tool.
  4. Choose the sender whose emails you want to flag (star) automatically.
  5. Click the toggle next to the Add Star to New Messages option to enable it.
  6. Automatically star messages in Outlook with Clean EmailAutomatically star messages in Outlook with Clean Email
  7. A dialog box will appear asking if you’d like to apply this action to existing messages from this sender. Click Confirm if you’d like to and you are done!
  8. Click Confirm to create the ruleClick Confirm to create the rule

All new messages from this sender will be starred (flagged) automatically when they arrive, making it easy to locate them in the Starred folder on the left panel.

Email mark as Starred to easily find them when neededEmail mark as Starred to easily find them when needed

💡 Note: Clean Email is not an email client and it can not create tasks for follow-ups and set reminders by flagging messages. However, it is an advanced inbox management tool with highly customizable automated rules and unique features to boost email productivity. For example, it allows setting up rules to flag (star) incoming emails from a number of senders or matching specific criteria automatically when they arrive, while this option isn’t available in Outlook rules on the web.

This is just one example of how Clean Email makes advanced inbox management effortless. You can also use the inbox organizer to easily apply automatic rules to messages in different Smart Folders (predefined filters that group similar emails together), unsubscribe from unwanted newsletters and other marketing emails, delete all but the single newest message from a sender, and much more.

Smart Views feature in Clean EmailSmart Views feature in Clean Email

The app is smart enough to make Cleaning Suggestions based on previously cleaned messages, and it will keep you up-to-date about all the actions taken to keep your mailbox clean so that you always know for sure that your automation rules are being applied as they should.

Quick Clean feature in Clean EmailQuick Clean feature in Clean Email

Wondering to learn more tips about cleaning your inbox? Check out our other guides on how to mark an email as important in Outlook, how to automatically mark as spam Outlook messages, and how to mark all emails as read in Outlook.

How To Flag An Email In Outlook - FAQs

What does it mean to flag an email in Outlook?

Flagging an email in Outlook means marking it with an icon to visually indicate its importance and creating a follow-up task in Microsoft To Do.

What happens when you flag an email in Outlook?

The message is marked with a flag icon and, optionally, a task is created, prompting you to reply to the message or take some other action.

How to find flagged emails in

You can find all flagged emails by clicking the Filter button above the list of your messages and choosing the Flagged option.

Is it free to flag messages in Outlook using Clean Email?

Yes, you can flag messages in Outlook using Clean Email for up to 14 days without paying, and you don't even need to provide your credit card information.

Can I create an email rule to flag emails in Outlook?

Yes, you can create a rule to automatically flag emails in the desktop version of Outlook. Unfortunately, the same can't be done in the web version, so those who rely on it should use Clean Email instead.

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