In the US. When you first sign up you are initially placed in a free trial. After the free trial period ends you fallback to the free tier. While in the free trial period I received one phone call which I let go to voicemail and besides the emails welcoming me to Oracle Cloud and regarding account creation I received 3 or 4 reminding me that the trial was ending and I would revert to the free tier. Since then, which has been months, I haven't received either calls or emails.