Yes. Caller ID not with=held, it just not displayed. Like if the phone called emergency services, the caller information would be shown to them. The phone company will known caller information. Each phone company have different codes so have to check with your company what right code is. But you flag the call for tracing and phone company will NOT give caller information to you but it will give to police if they ask for it. The trace code is way for phone company to know which call it was.