The South African Multiple Option Settlement (SAMOS) system was introduced on 9 March 1998. The SAMOS system is an automated interbank settlement system provided by the South African Reserve Bank for banks to settle their obligations on an immediate real-time basis, or in a delayed settlement arrangement, providing guaranteed settlement. Large-value payments are settled one-by-one on a real-time gross settlement (RTGS) basis, while retail payments are settled as a batch on a deferred basis. Settlement is final and irrevocable and is based on Credit Push principle. The SAMOS system is linked to the various participant banks, clearing systems and operators.