How to use the Email Disk Usage tool in cPanel

Knowledgebase Article

How to use the Email Disk Usage tool in cPanel

Email has a habit of quietly piling up. Not just the important stuff, but the other stuff. Sent attachments you forgot about. Calendar invites from years ago. Automated notifications that felt important at the time. And, of course, the Sent folder, dutifully storing everything forever, just in case.

Before you know it, your mailbox is full to the brim.

You could upgrade your hosting plan - and sometimes that’s the right move. But if you don't want to keep six-year-old spam or a backlog of hefty attachments, you’re in the right place.

The good news? You don’t have to guess what’s using the space. cPanel includes a built-in Email Disk Usage tool that shows you exactly where your email storage is going — and lets you clean it up safely.

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See what’s using your email space

The Email Disk Usage tool shows how much space each folder in a mailbox is using, so you can quickly spot problem areas like large Sent folders or attachment-heavy mail.

To access it:

Log in to cPanel
Go to Email
Click Email Disk Usage
Select the mailbox you want to review

You’ll see a breakdown of folders such as Inbox, Sent, Trash and Spam, along with how much space each one is using.

Why mailboxes get big

Every copy of an email counts.

If you send a 10 MB attachment to five colleagues on the same hosting account:

One copy lives in your Sent folder
One copy lives in each recipient’s mailbox

That’s 60 MB of storage used by a single email.

This is why the Sent folder is so often the biggest surprise. Most email clients never clean it automatically, and replies usually include the message you originally sent, so keeping Sent emails from years ago often adds little value.

If you’re hesitating here, that’s completely normal. Email slowly turns into a record-keeping system by accident, especially if you’ve never organised things into folders.

A couple of habits can make a big difference going forward:

Avoid sending large files as attachments if it’s a regular thing. Services like Dropbox, Google Drive, or WeTransfer let you share a link instead - one copy stored, not many.
Check your email signature. If it includes embedded images rather than images loaded from a URL, every email you send becomes heavier. Multiply that by dozens of emails a day and it adds up quickly.

Small changes like these won’t fix an overflowing mailbox overnight, but they do stop the same problem quietly rebuilding itself.

Cleaning up safely

Next to each folder, the Email Disk Usage tool lets you delete messages in bulk.

If you’re unsure where to start, this is a sensible approach:

Empty Trash and Spam
Review Sent for very old or very large messages
Clear automated folders you no longer need
Leave Inbox until last

This lets you reclaim space without touching things you’re actively using.

Understanding the deletion options

When selecting messages to delete, you’ll see a dropdown with several options. These control which emails are targeted in that folder.

1 year old or more
Selects emails that are at least one year old. A safe starting point for Sent items and automated mail.
30 MB in size or more
Targets emails with large attachments. Often a quick win - deleting a few big messages can free a lot of space.
Previously viewed
Selects emails that have already been opened. Useful if you want to avoid deleting unread messages.
All messages
Selects everything in the folder. Best used for Spam, Trash, or folders you no longer need.

Custom query (optional, but powerful)

The Custom query option allows more precise targeting using the same search language as the mail system behind cPanel (Dovecot). This is optional — most people won’t need it — but it can be very useful.

Examples:

Delete mail older than 2 years:
before 2024-01-01
Delete emails larger than 10 MB:
larger 10M
Delete emails with “Invoice” in the subject:
subject "Invoice"
Delete mail from a specific sender:
from [email protected]
Combine conditions:
larger 5M before 2023-01-01

This targets emails larger than 5 MB that are also older than 1 January 2023.

For full reference, see the Dovecot documentation.

When cleaning up isn’t enough

Sometimes email usage is genuinely high - shared mailboxes, lots of attachments, or record-keeping requirements.

If you’ve tidied up and are still hitting limits, options include:

Upgrading your hosting plan
Adding a Mailbox Boost (on Performance plans and above)
Moving heavy email usage to a dedicated email solution

Take a look at this article to understand your upgrade options. If you’re unsure what makes sense, we’re happy to help you choose the most cost-effective route.

In summary

Email doesn’t get messy overnight. It creeps.

The Email Disk Usage tool helps you:

See exactly what’s using space
Clean up with confidence
Avoid unnecessary upgrades

A little housekeeping now saves a lot of stress later, and your future self will thank you.