How do I cancel my subscription on Kindle?

Change Subscription Settings

Change your magazine or newspaper subscriptions from the Subscription Settings page of Manage Your Kindle.

Go to www.amazon.com/manageyourkindlesubscriptions

On the Subscription Settings page, click the Actions button next to the title to do either of the following:
Deliver past issue to my... - Deliver past issues of subscription content to a compatible Kindle device or Kindle reading app.
Note: To deliver past issues of a canceled subscription, select View inactive subscriptions, click the Actions button, and then click Deliver past issues to my....

Cancel Subscription / Reactivate Subscription - Cancel your existing subscription, or reactivate an inactive subscription.
Download & transfer past issue via USB - Download an issue of a subscription to your computer and transfer it to your Kindle device via USB.
Click Edit to manage your payment information and to determine the device or reading app where all future editions should be delivered.

More information on changing your subscription can be found here: http://www.amazon.com/gp/help/customer/display.html?nodeId=201265770