For email threads that involve only you and one other person, grouping similar topics can make things easier — but when you’re reading, moving, or deleting messages with many people in the thread, Conversation View can get confusing. When you turn it off, each message displays separately and in chronological order.
How Conversation View Works in Gmail
With Conversation View enabled, Gmail groups and displays together:
Messages with the same subject line, disregarding prefixes such as “Re” and “Fwd. " Up to 100 emails at a time.
When the subject line changes or a conversation reaches 100 emails, Gmail starts a new conversation.
How to Toggle Conversation View On and Off in Gmail
The option for turning Conversation View on and off in Gmail is available in your account’s General settings:
Select the Settings gear in the upper-right corner of Gmail. Select See all settings from the drop-down menu. In the General tab, scroll down until you find the Conversation View section and select Conversation view on or Conversation view off. Select Save Changes at the bottom of the screen.