as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
system
is there any circumstance in which it is necessary to mark extra payments on a loan as going to principal and not interest?
user
it could be a couple of things besides extra principal: i seem to remember hearing that some (shady?) lenders would just pocket extra payments if you didn't specify where they were headed, but i've also been told that this just isn't true.
assistant