Herein, we investigate the product type and distribution during the synthesis of azido-functionalized larger polyhedral oligomeric silsesquioxanes (POSSs) using 3-chloropropyl- and chloromethyldimethylsilylethyl-functionalized T 8 , T 10 , and T 12 POSSs as precursors. Our findings indicate that cage rearrangement occurs for the 3-chloropropyl-functionalized POSS cages with a stability order of T 12 > T 10 > T 8 , while the chloromethyldimethylsilylethyl-functionalized POSS cages remain structurally intact after the nucleophilic substitution.