To access the FATCA (Foreign Account Tax Compliance Act) Registration Login Page, you need to follow these steps:
Once on the login page, you will need to enter your FATCA ID and access code to log in. If you are logging in for the first time, you will use a temporary access code provided to you. If you have forgotten your FATCA ID or access code, there is a link on the login page to assist you with retrieving or resetting it.
Sources:
Publication 5118 (07/2021)