A spreadlock that is based on a forward contract. It allows the holder to lock in a specific number of basis points (a spread) on top of the existing spread in the underlying swap. For example, the parties to the contract may agree to enter, in one year’s time, into a 4-year swap to the effect that one party pays LIBOR and the other pays 4-year the Treasury yield as of the commencement date, in addition to 25 basis points.