The present invention provides an aqueous composition for storage of red blood cells consisting essentially of: adenine dextrose at least one non-metabolizable membrane-protectant sugar and a specifically defined pH buffering system. Also provided are improved methods for preserving red blood cells and methds for increasing the viability, membrance retention, and recoverability while suppressing apoptosis, hemolysis, and post-reinfusion clearance of stored red blood cells which utilize the novel compositions.