As of November 2026, Gmail’s Undo Send is switched on for every account and can’t be turned off. By default you get 5 seconds to take a message back. You can raise that to 10, 20 or 30 seconds in the web version under Settings, See all settings, General, Send cancellation period. One thing has changed since this post was first written: the feature moved out of Gmail Labs in June 2015, so the old Labs steps below no longer work. They are kept as history, with the current path next to each one.
What Undo Send does
Gmail’s undo option doesn’t pull back an email that has already been delivered. It holds your message for a few seconds before sending it, and if you click Undo in that time, the message never leaves your account. When Undo Send first appeared as a Labs experiment in 2009, you got only 5 seconds to decide whether your email was up to scratch. The Gmail team later added 10, 20 and 30 second options, and those four choices are still the full list today.
| Setting | Value today |
|---|---|
| Status | Always on, can’t be disabled |
| Default window | 5 seconds |
| Options on the web | 5, 10, 20 or 30 seconds |
| Where to change it | Settings > See all settings > General |
| Gmail mobile apps | Undo prompt appears after sending; the web window setting doesn’t apply there |
How to turn it on (the original Labs steps, now history)
The original instructions started at the Labs icon. Gmail Labs was the testing area where Google tried out features before releasing them to everyone, and Undo Send stayed there for about six years. When Google announced its graduation on 22 June 2015, it made the feature available in Gmail settings. Anyone who already had the Labs version kept it switched on.
The old second step was to find the “Undo Send” option in Labs and enable it. That step is no longer needed, because the feature is now on for every account and there is no switch to turn it off.
After saving, you then went to the Settings link and chose your cancellation period. That part still works today, through a slightly different menu path:
- Open Gmail in a web browser on a computer.
- Click the gear icon in the top right, then click See all settings.
- Stay on the General tab and find Undo Send.
- Open the Send cancellation period menu and pick 5, 10, 20 or 30 seconds.
- Scroll to the bottom and click Save Changes. If you skip this, the old value stays.
Fixing mistakes before they land
With the window set to 30 seconds, an email sent in a hurry without the time-sensitive attachment can still be cancelled. Click Undo in the small notice at the bottom left of the screen, add the file or fix the typo, and send again with confidence. The notice also has a View message link if you want to check what went out.
There are a few limits worth knowing:
- Once the timer ends, the email has gone. Gmail has no recall feature for delivered messages, so 30 seconds is the most time you get.
- The setting applies to the web. The Gmail apps for Android and iPhone show their own Undo prompt straight after you tap Send. Changing the web setting doesn’t give you a longer window in the apps.
- For more time, schedule the email. Click the arrow next to Send and choose Schedule send. The message waits in your Scheduled folder until the chosen time, and you can edit or cancel it before then.
How Gmail compares with other email clients
The original post called Gmail the only web email client worth using, because no other client came close to its options and customization. That isn’t true for this feature anymore. The major clients have caught up, and the main differences now are the default window and how far you can extend it.
| Client | Undo Send | Default | Where to set it |
|---|---|---|---|
| Gmail (web) | Built in, always on | 5 seconds | Settings > See all settings > General |
| Apple Mail (iOS 16 and later, macOS Ventura and later) | Built in | 10 seconds (options: off, 10, 20, 30) | iPhone: Settings > Mail > Undo Send Delay; Mac: Mail > Settings > Composing |
| New Outlook for Windows and Outlook on the web | Built in, adjustable slider | Varies by account | Settings > Mail > Compose and reply > Undo send |
| Classic Outlook for Windows | No Undo button | Not applicable | Use a rule that delays outgoing messages |
Gmail still has one of the shortest default windows of these clients. If you’ve never changed it, 30 seconds is the better setting for almost everyone, because the only cost is a short delay before each message actually goes out.
Thanks to Mashable for the inspiration.
FAQ
Can you unsend a Gmail message after 30 seconds?
No. Thirty seconds is the longest cancellation period Gmail offers, and after it ends the message is delivered to the recipient’s server. Gmail has no recall feature that removes an email from someone else’s inbox, so a quick follow-up correction is the only option left.
Does Undo Send work in the Gmail app on Android and iPhone?
Yes. After you tap Send, an Undo prompt appears at the bottom of the screen for a few seconds. You can’t change that window in the app, and the cancellation period you set on the web doesn’t carry over to mobile.
Can you turn off Undo Send in Gmail?
No. Since the feature left Labs, it has been on for every account. The shortest setting is 5 seconds, which keeps the delay to a minimum.
Does Undo Send work on campaigns sent through an email service provider?
No. Undo Send only affects messages you send from the Gmail interface. Campaigns sent through ESPs such as Mailchimp, Klaviyo or Brevo can’t be pulled back once delivery has started. That’s why test sends to your own Gmail, Outlook and Apple Mail inboxes, and a final check of links and personalization, matter before you hit send.
Does a longer cancellation period hurt deliverability?
No. Gmail just waits before handing the message off, so nothing about the message itself changes. Deliverability depends on things like SPF, DKIM and DMARC authentication and your spam complaint rate, not on how long you wait before sending.
Is Schedule send a better choice than Undo Send for important emails?
For high-stakes messages, it often is. Schedule send gives you minutes or hours to reread a message, while Undo Send gives you 30 seconds at most. Many people schedule important emails a few minutes ahead as a safety net and keep Undo Send for everyday typos.
Sources
- Google: How to undo send in Gmail for up to 30 seconds
- Microsoft Support: Undo Send in Outlook for Mac
- MacRumors: How to adjust the Undo Send delay in Apple Mail
- The Next Web: Gmail’s Undo Send feature finally graduates out of Labs after six years