When you sign up for Amazon Prime, your membership is set to automatically renew each year. You can turn off this automatic renewal at any time including during a free trial period.
To turn off this automatic renewal:
Note: Your membership will expire at the end of the current period.
Note: At the end of a free trial period, you'll be automatically upgraded to a paid annual membership for $79.
You can opt out at any time during the free trial period. For more information, go to Cancel Your Amazon Prime Membership.