Posted by JohnBoy on February 17, 2002 at 15:37:01:

If it was a credit line at 5.75% interest only, the annual interest on $85k would be $4,887.50. Divide that by 12 to get your monthly monthly payment which would be $407.29 interest only. At the end of a year you would still owe $85k since you only paid interest on that.

If the loan was amortized then it depends on the number of years the loan is amortized over.

If you paid $10k of the principal back in addition to the interest only payment, then you would take $75k x 5.75% = $4,312.50 annual interest, divided by 12 months = $359.37. This would be your new interest only payment each month until you paid more of the principal back.