To cancel your subscription, go to your account page. In the Renewal Information section, click Cancel Subscription.
After you cancel your subscription, Office will run in reduced functionality mode. That means you’ll still be able to open and print your documents but you won’t be able to edit them or create new ones. You’ll also lose access to the services that are included with your subscription like Office on Demand and Skype world minutes.
Later, if you change your mind and want to renew your subscription, go to your account page and click the yellow bar.