Monthly billing renews every month. Yearly billing is charged once a year and works out lower per month.
Cancel whenever you like
You can cancel from the Premium page in your account at any time. There is no cancellation fee.
Access after cancelling
After you cancel, Premium stays available until the end of the period you have already paid for, then your account returns to Free.
Full billing details are on the Subscription & Cancellation page. Premium gives you more tools for planning — it does not promise savings or any financial outcome.