An “option ARM” is typically a 30-year ARM that initially offers the borrower four monthly payment options: a specified minimum payment, an interest-only payment, a 15-year fully amortizing payment, and a 30-year fully amortizing payment.[4]
These types of loans are also called “pick-a-payment” or “pay-option” ARMs.
When a borrower makes a Pay-Option ARM payment that is less than the accruing interest, there is “negative amortization”, which means that the unpaid portion of the accruing interest is added to the outstanding principal balance. For example, if the borrower makes a minimum payment of $1,000 and the ARM has accrued monthly interest in arrears of $1,500, $500 will be added to the borrower’s loan balance. Moreover, the next month’s interest-only payment will be calculated using the new, higher principal balance.
Option ARMs are often offered with a very low teaser rate (often as low as 1%) which translates into very low minimum payments for the first year of the ARM. During boom times, lenders often underwrite borrowers based on mortgage payments that are below the fully amortizing payment level. This enables borrowers to qualify for a much larger loan (i.e., take on more debt) than would otherwise be possible. When evaluating an Option ARM, prudent borrowers will not focus on the teaser rate or initial payment level, but will consider the characteristics of the index, the size of the “mortgage margin” that is added to the index value, and the other terms of the ARM. Specifically, they need to consider the possibilities that (1) long-term interest rates go up; (2) their home may not appreciate or may even lose value or even (3) that both risks may materialize.
Option ARMs are best suited to sophisticated borrowers with growing incomes, particularly if their incomes fluctuate seasonally and they need the payment flexibility that such an ARM may provide. Sophisticated borrowers will carefully manage the level of negative amortization that they allow to accrue.
In this way, a borrower can control the main risk of an Option ARM, which is “payment shock”, when the negative amortization and other features of this product can trigger substantial payment increases in short periods of time.[5]
The minimum payment on an Option ARM can jump dramatically if its unpaid principal balance hits the maximum limit on negative amortization (typically 110% to 125% of the original loan amount). If that happens, the next minimum monthly payment will be at a level that would fully amortize the ARM over its remaining term. In addition, Option ARMs typically have automatic “recast” dates (often every fifth year) when the payment is adjusted to get the ARM back on pace to amortize the ARM in full over its remaining term.
For example, a $200,000 ARM with a 110% “neg am” cap will typically adjust to a fully amortizing payment, based on the current fully-indexed interest rate and the remaining term of the loan, if negative amortization causes the loan balance to exceed $220,000. For a 125% recast, this will happen if the loan balance reaches $250,000.
Any loan that is allowed to generate negative amortization means that the borrower is reducing his equity in his home, which increases the chance that he won’t be able to sell it for enough to repay the loan. Declining property values would exacerbate this risk.
Option ARMs may also be available as “hybrids,” with longer fixed-rate periods. These products would not be likely to have low teaser rates. As a result, such ARMs mitigate the possibility of negative amortization, and would likely not appeal to borrowers seeking an “affordability” product.
– Excerpt from Wikipedia
