Find and Delete Large Emails in Outlook Web (Fastest Way to Free Mailbox Space)

Large email attachments are the most common cause of a full mailbox. By finding and removing the biggest emails first, you can quickly free up 10–50GB of storage.

This guide shows how to locate and remove large emails using Outlook Webmail.

Step 1 – Open Outlook Webmail

1. Open your web browser.

2. Go to:

https://outlook.office.com

3. Sign in with your Microsoft 365 email address and password.

Step 2 – Search for Large Emails

At the top of Outlook, you will see the Search bar.

1. Click inside the Search box.

2. Type the following search:

3. Press Enter.

Outlook will now display emails larger than 10MB.

💡 These emails usually contain large attachments such as PDFs, images, or videos.

Step 3 – Sort by Size

To find the largest emails faster:

1. Click the Filter icon above the email list.

2. Choose:

Sort → Size

This will place the largest emails at the top.

Step 4 – Delete Unwanted Large Emails

1. Tick the checkbox beside emails you want to remove.

2. Click Delete in the toolbar.

These emails will move to Deleted Items.

You can also:

• Hold Shift to select multiple emails

• Hold Ctrl to select several emails individually

Step 5 – Empty Deleted Items

Emails still consume storage until they are permanently removed.

1. Open the Deleted Items folder.

2. Click Empty folder.

⚠️ Once deleted from this folder, emails cannot be recovered.

Step 6 – Check Sent Items for Large Emails

Many large emails are located in Sent Items because attachments are stored there as well.

1. Open the Sent Items folder.

2. Repeat the search:

3. Delete emails you no longer need.

Helpful Tip

You can adjust the search to find even larger emails:

Start with 20MB or higher to remove the biggest emails first.

Best Folders to Check

If your mailbox is close to full, review these folders first:

• Sent Items

• Inbox

• Deleted Items

• Junk Email

• Old project folders

Large attachments often accumulate in these locations.

Need Help?

If you require assistance cleaning up your mailbox or managing archived emails, please contact HealthyPC Support and we will be happy to help.