Abstract Reactivity studies of aluminoxane hydroxide and hydrogensulfide [{ Me LAl(EH)} 2 (μ‐O)] { Me L = CH[CMe(NAr)] 2 – (Ar = 2,4,6‐Me 3 C 6 H 2 ); E = O ( 1 ), S ( 2 )} with Group 4 amides led to the molecular heterobimetallic aluminoxanes [( Me LAlO) 2 (μ‐O){M(NR 2 ) 2 }] [M = Ti, R = Me ( 3 ); M = Zr, R = Me ( 4 ), Et ( 5 ); M = Hf, R = Me ( 6 ), Et ( 7 )] and aluminoxane sulfides [( Me LAlS) 2 (μ‐O){M(NR 2 ) 2 }] [M = Ti, R = Me ( 8 ), Et ( 9 ); M = Zr, R = Me ( 10 ), Et ( 11 ); M = Hf, R = Me ( 12 ), Et ( 13 )], respectively. The structural analyses of these compounds reveal six‐membered inorganic cores that exhibit Al–E–M (E = O, S; M = Ti, Zr, Hf) moieties. Compounds 10 – 13 exhibit strong O ··· M (M = Zr, Hf) transannular bonding, whereas 8 and 9 exhibit relatively short Ti–S bond lengths. DFT calculations performed on 8 – 13 at the B3LYP/LANL2DZ level of theory indicate that the titanium atoms in 8 and 9 , despite having the lowest transannular bond index, have the highest total Wiberg bond indexes. This can be rationalized in terms of the high Ti–S bond indexes, which indicate an important degree of electron density delocalized from the sulfur atoms to the titanium atom.