How Do I Turn Off iPhone Group Text Message Notifications?
Yes, if you are being bombarded with messages from a group chat or even an individual, it is possible to disable iOS alerts & notifications for a conversation.
Open the Messages app on your iOS device and navigate to the screen that displays a list of all conversations. Find the conversation that you would like to mute and swipe left on it. Two options will appear: Hide Alerts or Delete. Tap Hide Alerts and you will no longer receive notifications for new messages in that thread. You will, however, still receive notifications for other messages.
If you ever need to un-mute a thread you should again swipe left from the conversation list in the Messages app. Muted conversations will have an option that says Show Alerts that can be tapped to re-enable notifications.