How to set up an out-of-office reply in Gmail
Gmail's Vacation responder automatically replies to incoming emails while you're away. You can set a start and end date, write your message, and choose whether it goes to everyone or just people in your contacts. These steps use Gmail in a desktop browser.
Open Gmail in your browser and sign in if prompted.
Click the Settings cog icon near the top right of the page.
Click See all settings.
Make sure you're on the General tab. Scroll to the bottom of the page to find the Vacation responder section.
Select Vacation responder on.
Set the First day — the date the auto-reply starts sending. If you want it to stop automatically, tick the Last day box and set an end date.
Fill in the Subject field. Something like Out of office: back on [date] is clear and sets expectations immediately.
Write your message in the body field. At minimum, include when you'll be back and who to contact urgently if you have a colleague covering for you.
Decide who receives the auto-reply. Tick Only send a response to people in my Contacts if you'd rather not reply to newsletters, mailing lists, or cold emails automatically. Leave it unticked to reply to everyone.
Click Save Changes at the bottom of the page. A yellow banner will appear at the top of your inbox confirming the vacation responder is active.
Variations
Turning it off early
If you're back sooner than planned, go to Settings › General › Vacation responder, select Vacation responder off, and click Save Changes. Alternatively, click End now in the yellow banner that appears at the top of your inbox while the responder is active.
Using a Google Workspace (work) account
The steps are identical, but your IT administrator may have restricted the vacation responder or pre-set how it handles external senders. If you don't see the option at all, check with whoever manages your organisation's Google account.
Setting an out-of-office on the Gmail mobile app
Open the Gmail app, tap the Menu (three horizontal lines), tap Settings, select your account, then tap Vacation responder. The same options are available as on desktop.
Troubleshooting
Someone says they didn't receive an auto-reply
Gmail only sends one auto-reply per sender every four days, regardless of how many emails they send. If someone emailed you, received a reply, then emailed again within four days, they won't get a second one. This is by design and can't be changed.
The yellow banner has disappeared but I'm not sure if it's still on
Go to Settings › General and scroll to the Vacation responder section. It will clearly show whether it's on or off and display the dates you set.
The auto-reply is sending from the wrong address
If you send email from multiple addresses in Gmail (using the "Send mail as" feature), the vacation responder sends from your default address, not necessarily the one the incoming email was sent to. If this matters, you may need to adjust which address is set as default under Settings › Accounts and Import › Send mail as.
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