Yes, you must report the interest you made in 2025. U.S. taxpayers are taxed on worldwide income, even if the interest is compounding and not paid out. If the foreign bank didn't issue a statement or tax form, you are still required to report the interest that accrued from April–December 2025 as foreign interest income.
Depending on the account balance, you may also have FBAR (FinCEN 114) and Form 8938 filing requirements.
Because your 2025 return is already filed, you would file an amendment to add the missed interest.
Amend TurboTax Online
Amend TurboTax CD/Download
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"