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How to delete thousands of emails in Outlook

You have years of mail in Outlook or Hotmail and you want most of it gone. Clicking through it a screenful at a time isn't a plan. Here's every built-in way to delete in bulk, and the catches that make big deletes stall.

Updated October 14, 2026 · Outlook.com, Hotmail, new Outlook, classic Outlook

Short answer: To wipe a whole folder, open it, tick the checkbox above the message list and choose Empty folder. To delete everything from one sender, use Sweep. To clear old mail by age, use Settings › Account › Storage (on some accounts, Settings › Subscription › Email storage), which can permanently delete items older than 3, 6 or 12 months per folder. Then empty Deleted Items, because deleted mail keeps counting against your storage until you do.

Pick the right method

"Delete thousands of emails" means different things depending on what you're trying to get rid of. Matching the method to the job saves a lot of clicking:

You want to delete…UseWhere it works
Everything in a folderEmpty folderOutlook.com, new Outlook
Everything from one senderSweepOutlook.com, new Outlook (not classic)
Everything matching a searchSearch + select + delete, in roundsAll versions
Everything older than a few monthsSettings › Account › StorageOutlook.com
Old or large items, desktopMailbox CleanupClassic Outlook for Windows

Whichever you use, finish by emptying Deleted Items.

Empty an entire folder

This is the fastest way to remove thousands of messages, because it doesn't depend on how many messages are loaded on screen. Microsoft's steps for Outlook.com:

  1. Go to the folder you want to empty.
  2. Select the check box above the message list.
  3. In the reading pane, select Empty folder. All of the folder's email moves to Deleted Items.

Focused Inbox catch: if you use Focused Inbox, Microsoft notes you need to empty the Focused and Other tabs separately.

Emptying your actual Inbox is drastic. A safer pattern: move the mail you want to keep into a folder first (or archive it), then empty what's left.

Select All, and why it stops short

The obvious approach is to tick the select-all checkbox and press Delete. In a short folder it usually works. The problem shows up when you're working with a long list or a search with thousands of results.

Users report that in Outlook on the web and the new Outlook, select-all only selects the messages currently loaded in the list, often about 75 at a time. In a Microsoft Q&A thread, the accepted answer says that "based on our tests," the new Outlook "only selects visible emails (up to 75)" when you use Select All. Another user in a 2026 thread describes having to search, delete 75, search again, and repeat.

Microsoft doesn't document this number on its support pages, and the behavior may change between updates, so treat 75 as a reported figure rather than a fixed rule. The practical takeaways:

Search is the most flexible option: you can find mail by sender address, subject words, or keywords like a store name, then delete what matches.

  1. Type the sender's address or a keyword in the search box at the top of Outlook.
  2. When the results load, use the select-all checkbox at the top of the results.
  3. Press Delete.
  4. Run the search again and repeat until nothing is left.

Because of the select-all behavior above, a search with 3,000 results can take dozens of rounds. If the search is really "everything from this sender," Sweep is usually faster.

To skip Deleted Items entirely and delete permanently, Microsoft says you can select the messages and press Shift + Delete. Be sure, because permanently deleted mail is harder to get back.

Sweep: everything from one sender

Sweep is Outlook's built-in bulk tool for a single sender. Microsoft describes it as giving you "options to automatically delete all incoming email from a particular sender, to keep only the latest email, or to delete email older than 10 days."

  1. Select an email from the sender whose messages you want to delete.
  2. On the menu bar, select Sweep.
  3. Choose how to handle that sender's mail (delete everything from them, keep only the latest, or delete older than 10 days).
  4. Select Sweep to run it.

Limits worth knowing:

We cover Sweep in detail, including why it sometimes doesn't work, in Outlook Sweep not working, and the full one-sender workflow in how to delete all emails from one sender.

Delete by date with the Storage page

If the goal is "delete everything older than a year" rather than "delete this sender," Outlook.com has a storage page built for that. Microsoft says the Storage page (Settings › Account › Storage (on some accounts, Settings › Subscription › Email storage)) shows "a breakdown of how much space each folder in your mailbox is taking," with the option "to permanently delete all items (or those older than 3, 6, or 12 months) in these folders to free up space."

  1. In Outlook.com, open Settings and go to Storage.
  2. Find the folder you want to clean up in the list.
  3. Choose to delete all items, or only those older than 3, 6, or 12 months.

This is permanent. The Storage page's option is described as permanently deleting items, not moving them to Deleted Items. Use the 12-month option first if you're unsure.

The Storage page groups by folder, not by sender, so it won't tell you which senders are filling a folder. For that, see how to see who sends you the most email in Outlook.

Classic Outlook for Windows

Classic Outlook doesn't have Sweep, but it has its own bulk tool. Microsoft calls Mailbox Cleanup "a one-stop-clean-up tool you can use to trim the size of your mailbox":

  1. Choose File › Tools › Mailbox Cleanup.
  2. Use it to view the size of your mailbox and individual folders, find items older than a certain date or larger than a certain size, and view and empty your Deleted Items folder.

Classic Outlook also handles big selections in a normal folder view: click into the message list, select everything with Ctrl + A, and delete. With very large selections, give it time. Users report that deleting thousands of messages at once can make the app unresponsive for a long while, so breaking it into chunks is less painful.

Empty Deleted Items (or nothing changes)

This is the step people skip, and it's why "I deleted 10,000 emails and my storage didn't change" is such a common complaint. When you delete from your Inbox or other folders, items go to Deleted Items, and Microsoft says that folder "counts against your mailbox storage quota until it is manually emptied or the emails are automatically deleted after 30 days, whichever happens first."

  1. Open your Deleted Items folder.
  2. Above the message list, select Empty folder.

To go one step further, Microsoft says deleted email moves to a Recoverable Items store, and to permanently erase it you need to purge that too: under Folders select Deleted Items, select Recover items deleted from this folder at the top of the list, then select Empty folder. Microsoft warns that items removed from Recoverable Items "are permanently deleted and cannot be restored."

Storage numbers can also lag. For files deleted from OneDrive, Microsoft says it "might take up to 24 hours for your quota to update," so re-check later if the number hasn't moved. If your storage still looks full, our guide on Outlook storage full after deleting everything covers the other causes, including attachments that count toward your cloud storage.

When big deletes stall or mail comes back

Microsoft acknowledges that very large deletes don't always go smoothly. Its own tips for Outlook.com:

In practice: delete in smaller batches, keep the tab open, and if messages reappear, wait a while and repeat.

On your phone

Phones are the hardest place to bulk delete. For Outlook.com in a mobile browser, Microsoft's steps are: press and hold a message to select it, tap Select All at the top of the screen, then tap the trash icon.

In the Outlook mobile apps, users report it's harder. In one Microsoft Q&A thread a user couldn't select search results to delete them at all, and others ask where the "select all" control is. If you have thousands of messages to clear, a computer and Outlook.com in a browser will be much faster.

FAQ

Why does Select All in Outlook only delete some of my emails?

Users report that in Outlook on the web and the new Outlook, the select-all checkbox only selects the messages currently loaded in the list, often around 75 at a time, so a search with thousands of results has to be deleted in rounds. Microsoft does not document an exact number. To clear a whole folder at once, use Empty folder instead.

I deleted thousands of emails. Why didn't my storage go down?

Deleted mail moves to the Deleted Items folder, which still counts toward your mailbox quota until you empty it.

Why do deleted emails come back in Outlook.com?

Microsoft says that if deleted email comes back, it could be because you have deleted a lot of email recently, and suggests trying again later. If a large delete keeps failing, Microsoft recommends selecting a smaller batch.

Built-in tools work, but they make you choose between whole folders and one sender at a time. That's the gap PurgeInbox is being built to close.

Sources

Delete thousands of emails without deleting them batch by batch

PurgeInbox (in development) will rank your Outlook senders by volume so you can clear the biggest ones in a few clicks. Get one email when it launches.