Prevent email signature from being inserted when replying Is there a way to prevent Mail.app on OS X from auto inserting your email signature when replying to a message?
I believe you can create a template for a new email (which would include you signature) and then leave signatures off everywhere else by setting our signature to none.

The template can be a draft message or a sent message. Either way you have the option of sending them again, which makes them de facto templates.