A Balloon loan is a shortterm mortgage that has similar features of a fixed rate mortgage. A balloon payment mortgage is a mortgage which does not fully amortize over the term of the note, thus leaving a balance due at maturity.This tool figures a loan's monthly and balloon payments, based on the amount borrowed, the loan term and the annual interest rate. A balloon loan is a short-term loan that does not fully amortize over its term. This calculator computes the payment amount necessary for a mortgage with a balloon payment, using monthly interest compounding and monthly payments. Attached to this transmittal are the various bond documents for.