Outlook groups

Hi Barren, 

Thank you for reaching out. 

Based on your description of 12 groups that each hold 25 recipients and are used for sending email, you are most likely referring to Contact Groups (also called contact lists), which are saved collections of email addresses stored in the People area of Outlook. There is no single merge button, but you can consolidate all 12 into one new group by following the steps below. 

1. In Classic Outlook, select People from the side panel. 

2. Select New Contact Group from the ribbon and enter a name. 
3. Select Add Members, then choose From Outlook Contacts or From Address Book. 
4. Add each of your 12 existing Contact Groups directly as members of the new group. This nests them inside the new one. 
5. Select Save & Close when finished.

I hope this information is helpful. Please follow the steps above and let me know if it works for you. If not, we can continue working together to resolve the issue.  

If you found the response useful, please consider marking it as accepted, as this may help other community members who are looking for similar guidance.  

Thank you for your patience and understanding. I look forward to continuing the conversation.  

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