The molecular nickel complexes trans-diazido-tetrakis(pyrazole)nickel(II) and trans-diazido- tetrakis(3-methylpyrazole)nickel(II) feature terminal monohapto-bound azide ligands. The pyrazole (pyr) ring planes are aligned along the Nazide-Ni-Nazide axis by intramolecular N-H···Nazide bonds. The crystal packing is controlled by π-stacking between both pyrazole rings and azide ligands, N-H···Nazide hydrogen bonds, and intermolecular N-H-πpyr and C-H···N/πazide interactions.