Amazon Prime is a paid subscription service that provides eligible Amazon members with a plethora of exclusive benefits, including free two-day shipping and access to on-demand music and videos. For the 100 million people already using the service, Amazon Prime is a great way to make the most out of your Amazon account. But how much does the service actually cost to use? When Amazon first introduced the service in 2005, it cost $79 a year for free shipping within the contiguous United States.