By Default in Gmail, each time when you send, forward and reply to someone, it will automatically saves details of that person to your Address book or contact list. However most people like it because it can help recover forgotten addresses of former teachers, bosses, and people you contacted once but never thought you’d need to contact again.
But if you are a prolific email user who receive lots of email from different people, and if you diligently reply to them all, your contact book must have grown to unmanageable proportions.
How to Stop Gmail From Automatically Adding Contacts to your Address Book:
- Login to you Gmail Account.
- Select the settings page in your Gmail account.
- Under settings page, you can find the General tab.
- Scroll down the page until you come to the entry “Create contacts for auto-complete”, and switch from the default “When I send a message to a new person, add them to Other Contacts so that I can auto-complete to them next time” to “I’ll add contacts myself”.

- Click Save the changes before you leave the page.