Negative amortization

In finance, negative amortization (also known as NegAm, deferred interest or graduated payment mortgage) occurs whenever the loan payment for any period is less than the interest charged over that period so that the outstanding balance of the loan increases. As an amortization method the shorted amount (difference between interest and repayment) is then added to the total amount owed to the lender. Such a practice would have to be agreed upon before shorting the payment so as to avoid default on payment. This method is generally used in an introductory period before loan payments exceed interest and the loan becomes self-amortizing. The term is most often used for mortgage loans; corporate loans with negative amortization are called PIK loans.

Amortization refers to the process of paying off a debt (often from a loan or mortgage) over time through regular payments. A portion of each payment is for interest while the remaining amount is applied towards the principal balance. The percentage of interest versus principal in each payment is determined in an amortization schedule.

Negative amortization only occurs in loans in which the periodic payment does not cover the amount of interest due for that loan period. The unpaid accrued interest is then capitalized monthly into the outstanding principal balance. The result of this is that the loan balance (or principal) increases by the amount of the unpaid interest on a monthly basis. The purpose of such a feature is most often for advanced cash management and/or more simply payment flexibility, but not to increase overall affordability.

Neg-Ams also have what is called a recast period, and the recast principal balance cap is in the U.S. based on Federal and State legislation. The recast period is usually 60 months (5 years). The recast principal balance cap (also known as the "neg am limit") is usually up to a 25% increase of the amortized loan balance over the original loan amount. States and lenders can offer products with lesser recast periods and principal balance caps; but cannot issue loans that exceed their state and federal legislated requirements under penalty of law.

A newer loan option has been introduced which allows for a 40-year loan term. This makes the minimum payment even lower than a comparable 30-year term.

All NegAM home loans eventually require full repayment of principal and interest according to the original term of the mortgage and note signed by the borrower. Most loans only allow NegAM to happen for no more than 5 years, and have terms to "Recast" (see below) the payment to a fully amortizing schedule if the borrower allows the principal balance to rise to a pre-specified amount.

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