DEFINITION of 'Amortizing Swap'
An exchange of cash flows, one of which pays a fixed rate of interest and one of which pays a floating rate of interest, and both of which are based on a notional principal amount that decreases. In an amortizing swap, the notional principal decreases periodically because it is tied to an underlying financial instrument with a declining (amortizing) principal balance, such as a mortgage.
BREAKING DOWN 'Amortizing Swap'
The notional principal in an amortizing swap may decline at the same rate as the underlying or at a different rate which is based on the market interest rate of a benchmark like mortgage interest rates or the London Interbank Offered Rate. The opposite of an amortizing swap is an accreting principal swap - its notional principal increases over the life of the swap. In most swaps, the amount of notional principal remains the same over the life of the swap.