Form 8396 Mortgage Interest Credit is separate from Form 1098 Mortgage Interest Statement you receive from your bank or financial institution for mortgage interest paid.
Form 8396 is for holders of Qualified Mortgage Credit Certificates (MCC) issued by state or local governmental units or agencies. The certificate credit rate is shown on this certificate.
If you just have a Form 1098 and want to enter mortgage interest paid:
If you have a Qualified Mortgage Credit Certificate and need to complete Form 8396:
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the document at the time it is accessed.