How to unsend an email in Outlook (yep, it’s possible)

We’ve all done it. You hit “Send” on an email and then immediately wish you hadn’t. Maybe you forgot the attachment. Maybe you noticed a typo. Or maybe you accidentally sent it to the wrong person entirely.

Fortunately, if you’re using Microsoft Outlook, there’s a way to stop that email before it actually goes out. New Outlook and Outlook in a browser offer Undo Send, while Classic Outlook can use a delivery-delay rule. Depending on which version you’re using, that short pause can save your bacon.

So, let’s walk through how it works and how to set it up, plain and simple.

Why undo send is worth turning on

Emails are fast. Too fast, honestly. All it takes is one wrong click to send something you weren’t ready to share. A misspelled name, a missing invoice, or an email to your boss that was meant for your buddy, yikes! Mistakes like that happen all the time.

That’s exactly why the Undo Send feature is so helpful. It gives you a short window to cancel your email before Outlook sends it. While it’s not quite magic, it’s close enough when you’re trying to avoid an awkward moment, or a costly mistake.

Even better, it only takes a few seconds to set up. Once you do, it just works in the background, ready to step in when you need it most.

If you use Outlook in your web browser

Now, if you check your email through a web browser like Chrome or Edge, by logging into Outlook.com or Microsoft 365, you’re in luck. This version of Outlook includes a built-in Undo Send feature and setting it up is quick and easy.

Here’s how to get started:

1. Open Settings using the gear icon.
2. Select Mail, then Compose or Compose and reply.
3. Find Undo send and choose the longest delay offered.
4. Select Save if shown.

For personal Outlook.com accounts, Microsoft now documents a delay of up to 30 seconds. Use the options shown in your account rather than assuming every Outlook version has the same limit.

From now on, every time you send an email, you’ll see a little “Undo” button pop up at the bottom of the screen. If you click it quickly enough, Outlook cancels the pending send so you can correct the message.

So, if you realize something’s off, even just a second too late, you’ll still have time to stop it.

Using Classic Outlook (the old desktop app)

If you’re using the full desktop version of Outlook, the one folks have relied on for years, you won’t see an Undo button. However, you can still build in a safety net by creating a rule that delays every outgoing email.

To do that, just follow these steps:

1. Open File > Manage Rules & Alerts > New Rule.
2. Under the blank-rule templates, choose Apply rule on messages I send, then Next.
3. Leave the conditions unchecked. Select Next, then confirm Yes to cover every outgoing message.
4. Check defer delivery by a number of minutes.
5. Click the underlined number in the rule description, enter 1 or 2 minutes, then select OK.
6. Continue with Next, choose any exceptions, then select Next again.
7. Name the rule, check Turn on this rule, and select Finish. Select OK to close Rules & Alerts.

Once that’s in place, any email you send will sit in your Outbox for the amount of time you chose. During that short delay, you can delete it from the Outbox to cancel it. To make corrections, move it to Drafts, edit it, and send it again when ready.

Keep Classic Outlook running and connected. This is a rule that runs in the desktop app. It does not delay messages you send through Outlook on the web or another device.

Using new Outlook for Windows

Now, if you’ve switched over to new Outlook for Windows, things work a bit differently. Classic Outlook’s “defer delivery by a number of minutes” rule is not supported in new Outlook. Microsoft lists new Outlook’s delay-send support as partially available, so use its built-in sending settings rather than relying on a Classic Outlook rule.

Like the web version, new Outlook includes a built-in Undo Send feature. Microsoft’s new Outlook guidance describes a window of up to 10 seconds. Choose the longest delay offered in your settings.

To turn it on:

1. Open Settings > Mail > Compose and reply.
2. Find Undo send and choose your delay.
3. Select Save if shown.

After that, you’ll get a brief moment after hitting Send to stop the message from going out. Click Undo before the prompt disappears.

Need longer for a particular email? Select the arrow beside Send and choose Schedule send. This option is not available for IMAP or POP accounts in new Outlook.

What actually happens when you hit send?

So what’s going on behind the scenes? Outlook delays sending the message for your chosen interval. Undo Send lets you cancel during that window. In Classic Outlook, the delay rule holds the message in the Outbox for the number of minutes you chose.

Take a look at this simple visual:

As you can see, this short pause gives you just enough time to realize something’s off and stop the message before it’s too late. If you don’t hit Undo during that delay, the email goes out as usual.

What if the email has already been delivered?

For Microsoft 365 work or school accounts in Exchange Online, message recall can remove a delivered message from a recipient’s mailbox. It generally works within the same organization. Recall between different organizations requires a specific Exchange Online configuration set up by the receiving organization’s administrator. It cannot retrieve an ordinary email sent to a client’s Gmail or personal Outlook.com account.

In new Outlook or Outlook on the web, open Sent Items, double-click the message, select Recall Message, and confirm. Check the Message Recall Report to see the result. Exchange Online can also recall already-read messages when the organization permits it, but that cannot undo what someone has seen or copied.

Wrapping it up

So, how do you unsend an email in Outlook? That depends on which version you're using.

If you’re on the web or using new Outlook for Windows, turn on Undo Send and choose the delay available in your settings. Personal Outlook.com accounts now support up to 30 seconds. In Classic Outlook, use a rule to delay outgoing emails by one or two minutes. Set this up before you need it.

Either way, it’s a smart move. Just a few clicks can prevent embarrassing mistakes and make your email life a whole lot easier.

For small businesses and folks here in Southwest Oklahoma, this feature can be a real lifesaver. Whether you're emailing clients, vendors, or the local school board, it’s nice to know you’ve got a second chance if something slips through.

Need help figuring out which version of Outlook you have? Or want us to set this up across your whole office? Give us a shout, we’re happy to lend a hand.

Microsoft documentation

• Message recall and Outlook.com Undo Send
• Undo Send settings in new Outlook
• Delay rules and Schedule send
• New and Classic Outlook feature comparison
• Exchange Online cloud-based recall restrictions