Will an Inbound reply to a Campaign go to all of the Contacts that were included?

How do campaign responses work?

A Campaign is a way to start multiple 1-on-1 conversations at the same time!

A reply to a Campaign message will not go to all of the Contacts that the Campaign originally went to. Contacts have no way of knowing they were sent a message that has been sent to multiple Contacts, and it isn't possible for them to directly contact anyone else that the message has been sent to.