Based on your financial expertise, provide your response or viewpoint on the given financial question or topic. The response format is open.

does interest payment on loan stay the same if I pay early
It depends on the type of loan.  Fully amortized loans have a schedule of payments don't recalculate as you pay.  If you want to make an additional payment you need to contact the lender to apply your payment toward principle and reamortize the loan.  Otherwise all your additional payment will do is change the amount due on your next payment, or push out your next payment due date. Regarding interest calculation, you owe interest on the principle outstanding.  Say you have a 10 year loan (120 Months), at 5% APR, and a $1,000 payment (this means you borrowed roughly $94,000) Each month the amount of interest owed reduces because there is less principle outstanding.  The reason loans are amortized like this is so the borrower has a predictable, known, monthly amount due.