How to free up space in Hotmail and Outlook.com without losing old mail

To free up space in Hotmail or Outlook.com, empty Deleted Items, find your largest emails with Filter > Sort by > Size, and remove old mail that you no longer need online. Before you delete old mail that you want to keep, save a copy on your computer. This page is the hands-on step list. Hotmail and Live.com addresses are Outlook.com accounts, so the same steps work for all three. If you are not sure whether your mailbox or your cloud storage is full, start with Outlook storage full: what to do.

Before you start: two facts that change the plan

• There are two limits. A free account has 15 GB for email and 5 GB of Microsoft cloud storage. Microsoft says the cloud storage is shared by OneDrive and your Outlook.com attachments. If either one is full, you cannot send or receive email.
• Deleting is not the same as freeing space. A deleted email goes to Deleted Items and still counts until you empty that folder, or until it is removed after 30 days.

Step 1: See which folders use the space

Sign in to Outlook.com. Select Settings, then Account, then Storage. The page shows how much space each folder takes. Write down the three largest folders. You will check them again at the end.

The same page can permanently delete all items in a folder, or only items older than 3, 6 or 12 months. Do not use it on Inbox, Sent Items or Archive yet. You cannot get those emails back afterwards.

Step 2: Empty Deleted Items

Open the Deleted Items folder, select the emails and delete them. Look through the folder first. It sometimes holds an email you deleted by mistake.

• If you used Sweep: emails that Sweep removed do not reduce your storage until they are also deleted from Deleted Items.
• Junk Email empties itself. Outlook.com deletes items there after 10 days, so it rarely holds much.

Step 3: Find the biggest emails

Open a large folder. At the top of the message list, select Filter > Sort by > Size. If the smallest emails are at the top, select it again. A few emails with large attachments often use more space than thousands of short ones.

For each large email, decide:

• Not needed: select it and press Shift + Delete. This deletes it permanently, without the stop in Deleted Items.
• Only the file is needed: save the attachment to your computer, then delete the email. The attachment is only removed when the whole email is deleted.
• The email is needed: leave it for Step 4, which keeps a full copy before anything is deleted.

Microsoft also suggests Save to OneDrive, which appears beneath an attachment. Be careful with it. OneDrive uses the same 5 GB of cloud storage as your attachments. If cloud storage is your problem, moving files there does not help.

Step 4: Keep a local copy of old mail

Steps 1 to 3 free space by throwing things away. For years of mail that you might need again (receipts, contracts, letters, photos from family), make a copy on your computer first. Then you can delete it online without losing it.

MailVault is one way to do this. It is free and runs on macOS, Windows and Linux.

1. Download MailVault and open it. Use version 2.19.1 or later: archiving Outlook.com accounts works from that version on.
2. Choose Add Account, then Outlook / Microsoft 365, and type your Outlook.com, Hotmail or Live.com address.
3. Select Sign in with Microsoft and finish the sign-in in your browser. When you come back, MailVault adds the account. You do not type a password into MailVault, and there are no server settings to enter.
4. Open the folder you want to clear. Select the checkbox at the top of the message list (its label is Select messages…). In the dialog, pick a year under By Year, or set a Custom Range, and go on. If the dialog says that only some emails are available locally, let the folder finish loading in MailVault and try again.
5. Choose Archive. It copies the emails into your vault, and they stay on the server too.

Now check the copy. In the sidebar, switch the folder list to Vault. Open a few of the oldest emails, open an attachment or two, and search for something you remember. Each email is saved as a standard .eml file on your computer, so other mail apps can open it too.

Step 5: Delete the old mail from Outlook.com

When you are sure the copy is good, you have three ways to remove the mail from the server.

• Free, in MailVault: select the same emails again and choose Delete from Server. It removes the server copy only. Emails already in your vault keep their copy.
• Premium, in MailVault: Archive & Delete does Step 4 and Step 5 at once. It copies each email into your vault, checks that the copy is there, and only then removes it from the server. An email that fails the check stays on the server. For a whole account, Settings > Backup & Restore > Archive & delete clears the folders and years you choose.
• In Outlook.com: delete the same emails there. Use the same dates you archived, so you do not delete mail that has no copy.

Step 6: Empty Deleted Items again, then wait

Mail you delete, in Outlook.com or from another app, can land in Deleted Items first. Open Deleted Items in Outlook.com and empty it again. Then go back to Settings > Account > Storage and compare with the numbers you wrote down. Microsoft says changes can take up to 24 hours to show, so do not delete more just because the number has not moved yet.

What each step removes

What not to delete

• Anything you have only one copy of. Receipts, invoices, tax papers, contracts, warranties, medical and legal letters. Archive them first.
• Emails that prove you own something. Software license keys, domain and account sign-up emails, and order confirmations can be hard to get again.
• Attachments that exist nowhere else. Photos and documents that someone sent you once, and that you never saved.
• Whole folders by date with the Storage page option, unless you have a copy of that folder.
• Your local copy. After you delete mail from the server, the copy in your vault is the only one. In MailVault, Unarchive deletes the vault copy, and Delete Everywhere removes the email from the server, your vault and your backup drive. Keep a second copy on another drive if the mail matters.

Deleted Items is not a backup. Microsoft removes items there after 30 days.

Frequently asked questions

What to do next

Do Steps 1 to 3 today to get under the limit. Then copy your old mail to your computer and delete it online in batches, one year at a time. To compare other ways to make that copy on a Mac, read how to back up Outlook.com email to a Mac. The same method works for Gmail and other providers, as explained in how to free up email storage without losing old emails. If you are thinking about Microsoft 365 instead, see archiving locally vs paying for more storage.

Outlook.com steps and limits are from Microsoft Support: Storage limits in Outlook.com and Check email and cloud storage. Last checked: October 2026. For a shorter overview, see Outlook.com or Hotmail mailbox full.