When Should You Use High Importance in Outlook?
Marking an email as high importance should be reserved for truly time-sensitive or business-critical matters. Use it in situations like:
- You need a reply within a few hours
- You're sending legal or deadline-driven documents
- You’re notifying someone of an emergency or disruption (e.g., IT outage)
💡 Avoid overusing high priority. If every message is flagged, people may start ignoring the alerts. Save it for when it truly counts.
Can You Change the Importance After Sending?
No. Once you send an email, you cannot change its importance level. This is a known limitation in Outlook and confirmed by Microsoft.
💡 If you realize you forgot to mark something as urgent, the best option is to send a follow-up message with the correct priority or call attention to the original.
What’s the Difference Between Important, Flagged, and Pinned Emails?
Outlook has multiple ways to keep track of emails, and each has a specific purpose:
| Feature | What it does | Who sees it? |
|---|---|---|
| High Importance | Adds a red exclamation mark to the message | Seen by the recipient |
| Flag | Adds a red follow-up flag to your own inbox | Seen by you, not recipient |
| Pin | Keeps an email at the top of your inbox (Outlook web only) | Seen by you (web view) |
❗ Why Is There a Red Exclamation Mark in Outlook?
The red exclamation mark in Outlook usually appears next to an email in your inbox or when composing a message. It indicates that the message has been marked with high importance by the sender.
Here’s what it means depending on where you see it:
- In your inbox: If you see a red exclamation mark next to a message, the sender flagged it as high importance. It’s meant to get your attention and indicate the message may be time-sensitive or requires a quick response.
- When sending a message: You can mark your own email as high importance using the red exclamation mark icon in the Tags group on the ribbon. The recipient will then see the same red icon in their inbox.
Is There a Smarter Way to Manage Urgent and Non-Urgent Emails?
If you’ve tried marking emails as high importance in Outlook and still feel like your inbox is hard to manage, you’re not alone. Many users find that urgency gets lost when there’s too much noise.
Clean Email helps by offering a better way to highlight what’s important, without the pressure of manual sorting.
This isn’t about replacing Outlook—it’s about helping you get through it faster. When you don’t have to dig for what matters, you respond faster, miss less, and spend less time in your inbox overall.
Why Choose Clean Email?
- Enjoy the same functionality on mobile (Android and iOS) and desktop (Web and Mac).
- Automatically sort incoming messages by sender, category, or keyword.
- Use Smart Folders to view only key emails (like Top Senders, Financial and Insurance, or Unread).
- Enable the Screener feature to block unknown senders until you approve them, so only trusted messages reach your inbox.
- Create Auto Clean rules to filter non-urgent messages out of your way.
How to Send a High-Priority Email in Outlook Manually
By learning how to set email priority in Outlook before sending, you will be able to ensure that important messages get the attention they deserve. This can be particularly useful in a professional setting, where timely communication can make all the difference and other communication channels may not be available.
Desktop (Windows)
- Launch the Outlook desktop client.
- Click the New Email (or New Message) button from the Home tab in the toolbar.
- Click the red exclamation mark (High Imprtance) in the Message tab under the Tags section.
Desktop (Mac)
- Launch the desktop client application.
- Click the New Message button in the top toolbar.
- Click the Priority button located on the right from the Subject line.
- Choose High, Normal, or Low, and you are done!
Web
- Log in to Outlook.com.
- Click the New Mail button in the toolbar.
- Click the red exclamation mark in the Message tab.
- Choose High, Low, or Normal importance.
How to Mark Emails as Important in Outlook Automatically
Now that you know how to make an email important in Outlook manually, it's time for us to explain how to do the same automatically. Why? Because most important emails you receive probably come from the same few senders, so it makes sense to have Outlook automatically mark them as important.
Desktop (Mac)
- Launch the Outlook desktop client.
- Right-click on the message and choose Rules.
- Click the Create Rule… button.
- Specify the condition or conditions for the rule.
- Open the Do the following dropdown menu and select the Mark with importance option.
- Set the priority level to High.
- Click Save.
Desktop (Windows)
- Launch the Outlook desktop client.
- Navigate to the Home tab and click on the Rules button.
- Click the Manage Rules & Alerts option.
- Create a new rule by clicking the New Rule button.
- Start from a blank rule and select the Apply rule on messages I receive option. Click Next.
- Specify the condition for the rule and click Next. For example, you can configure the rule to trigger when you receive a message from a specific person or public group.
- Tell Outlook that you want to mark all matching messages as important. Then, click the underlined "importance" link in Step 2 and set the importance level to High.
- Click the Finish button.
Web
- Log in to Outlook.com.
- Click the Settings gear icon and click the View all Outlook settings option at the bottom.
- Navigate to Mail → Rules.
- Add a new rule.
- Name the rule and add at least one condition.
- Click the Select an action dropdown menu and choose the Mark with importance option. Then, set the importance level to High.
- Click Save.
From now on, your emails will be marked as important automatically. For better visibility, you can pin emails in Outlook to the top of your inbox using the Sort by importance option.
If you would like to have even more control over your Outlook.com email account and how your messages are displayed and organized, then you should connect your email account with Clean Email.
💡 Tip: You can also flag an email in Outlook to draw attention to it without necessarily marking it as high-priority.
How Does the Outlook High-Priority Marker Work?
The high-priority marker in Outlook is a feature that allows you to flag an email as important to ensure that it stands out in your inbox. When an email is marked as high priority, it will be displayed with a red exclamation mark next to it, which makes it easier for you to identify and prioritize it among other messages in your inbox.
More importantly, you can also mark an email as high priority in Outlook before sending it, which will indicate to the recipient that the message requires urgent attention. Just know that it's entirely up to the recipient to treat your message with the urgency you believe it deserves. What's more, not all email clients indicate message priority the same, and some don't indicate it at all.
💡 Note: Contrary to popular belief, the high-priority marker doesn't stop emails from going to spam in Outlook because spam filtering in Outlook and other email providers is a separate process that involves a set of algorithms and rules designed to identify and block unsolicited or unwanted emails.
Outlook High-Priority Marker Vs Gmail High-Priority Marker
The Outlook high-priority marker basically says, "Open this message right now! It's really urgent!" The Gmail high-priority markers (the star icon and the yellow Importance marker) are meant to visually signal that a message is important or urgent, but they also teach Gmail which messages it should mark as important automatically next time.
Outlook high-priority messages can be displayed using a smart folder. All Gmail messages that are marked as important using the star icon can be found in the Starred folder, while messages marked as important using the yellow Importance marker can be found under the Gmail Important folder.
💡 Tip: You can star messages from specific senders automatically in Gmail using Clean Email (more about it later in this article), and it takes just one click to set everything up.
How to Mark an Email as Important in Outlook - FAQs
Can you star important emails in Outlook?
Outlook doesn't have a "star" feature like some other email providers, but it does have a flagging system that can be used to mark important messages for better visibility and to urge their recipients to open them.
How do I make an email high priority in Outlook app?
To mark an email as high priority in the Outlook app, click the New Email button in the toolbar and then click the red exclamation mark in the Message tab.
How to move important emails to the top in Outlook?
You can move important emails to the top of your Outlook inbox by sorting your inbox by priority.
How can the Clean Email app help me avoid missing important emails?
The Clean Email app can help you avoid missing important emails by automating commonly performed email management tasks so that your inbox is always free of clutter.
How to send a high priority email in the Outlook mobile app?
Unfortunately, it's not possible to send a high-priority email using the Outlook mobile app at the moment.
