How is deferred interest calculated on an Optional ARM loan?

Question

Example:
Loan amount $200000
Minimum rate: 4.0%
Coupon rate: 7.0%
Type: 5-year fixed Hybrid ARM
Interest only payment

I know how to calculate the monthly payment, but have a hard time to find an online calculate to calculate deferred interests.

Answer 1

deferred interest is the amount you choose not to pay. If you paid the minimum 4%, and your actual ammortized rate is 7%, then 3% is your deferred interest and tacked on to your principal balance. .03*200,000/12= $500/month deferred interest

Answer 2

The deffered interest is the amount of interest accrued at the coupon rate minus the amount you actually pay. On your statement the optional payments will include the low payment, an interest only payment, and the regular 30 and fifteen year payments. You only deffer interest when you pay the low payment. The amount deffered is the interest only payment minus the low payment. This is eventually added to the balance of the loan. PS. be careful calling this a fixed loan. The low payment is fixed, but the coupon rate and thus your deferred interest are adjusting.