DEFINITION of 'Mortgage Rate Lock Float Down'
A mortgage rate lock with the option to reduce the locked interest rate if market interest rates fall during the lock period. A rate lock with a float-down option can provide the borrower with security against an increase during the rate lock period, while the float-down option allows the borrower to take advantage of a fall in interest rates during the lock period.
BREAKING DOWN 'Mortgage Rate Lock Float Down'
As with any financial option, float-down options on a rate lock have a theoretical value or cost; therefore, rate locks with a float-down option are more expensive than rate locks without. The option will only be exercised by the mortgagor if interest rates fall.