South Dakota Codified Laws
Chapter 08 - Oral And Written Contracts
Section 53-8-7 - Alteration of written contract without new consideration.

53-8-7. Alteration of written contract without new consideration.
A contract in writing may be altered by a contract in writing without a new consideration or by an executed oral agreement, and not otherwise.

Source: CivC 1877, §969; CL 1887, §3593; RCivC 1903, §1287; RC 1919, §908; SDC 1939, §10.0806.