Yes, you pay each month in advance. As you stated, your first billing period is pro-rated from when you signed up to the billing date. You are also charged services for the upcoming month in advance This occurs when anyone signs up with a provider. Similarly, when you change a plan, both the old plan and the new are pro-rated for the portion of the month they were active. Here’s link for you describing the process. http://help.koodomobile.com/my-bill/charges-explained Then go to "charges on my first bill"