Official Microsoft instructions: Send automatic replies (out of office) from Outlook - Microsoft Support

*If you are using Outlook New or Outlook on the web (OWA) scroll below for instructions

Outlook Classic

1. Search for "Automatic Replies" in Outlook
   
2. Enable automatic reply, you can also choose specific time frame you would like it enabled
   Anything in the text field below will be on automatic reply
   
3. Make sure you enable the automatic reply for senders outside of your Organization (Company) as well if needed
   You can choose different reply as well if needed
   

Outlook New & Outlook on the web (OWA)

1. Go into Settings on top right > Accounts > Automatic replies
   
2. Enable automatic reply, you can also choose specific time frame you would like it enabled
   Anything in the text field below will be on automatic reply
   
3. Make sure you enable the automatic reply for senders outside of your Organization (Company) as well if needed
   You can choose different reply as well if needed