When signing up for the monthly or yearly membership, yes, it will auto renew at the end of the paid subscription unless you manually stop your auto-renew in your account. Again, this is not a one time donation. Signing up for the online Posse account is a reoccurring subscription. However, you can manually cancel it at anytime.
Click here to find out how to Pause (also known as stop auto-renew) here.
