31 C.F.R. § 343.3
(d) Registered. To obtain redemption, a bond with the assignment for redemption properly completed and executed must be presented to the Division of Special Investments. Payment routing instructions must also be included with the bond at redemption. Upon partial redemption of a registered bond, the remaining balance will be reissued in book-entry form with the original issue and maturity date.
(Approved by the Office of Management and Budget under control number 1535-0127)