No, you will only use your parish code when you first sign up for Formed with the "Find your parish Subscription" option when you create an account for the first time under your parish at formed.org.  

If using this link automatically logs you into Formed, you are already signed into Formed under a parish. To update your parish please reach out to parishcare@formed.org. 

Every time after this, you will sign in with the "Sign In" button on Formed.org.