In the title 2:1 adduct, [Sn(2)W(2)(C(10)H(13)NO(2))(2)(CO)(10)](2)[W(CO)(6)], the complete hexa-carbonyl-tungsten mol-ecule is generated by a crystallographic inversion centre. The heterometallic mol-ecule features a central Sn(2)O(2) core with essentially equal Sn-O(eth-oxy) bond lengths. The second eth-oxy O and amine N atoms of each N,O,O'-tridentate ligand coordinate to one Sn atom only. The NO(3) donor atoms occupy basal positions and the W atom the apical position in a distorted square-pyramidal geometry for each Sn atom. The W atoms are approximately syn to each other but the central metal core is non-planar [W-Sn⋯Sn-W pseudo-torsion angle = 43.573 (16)°]. One of the carbonyl ligands in the heterometallic mol-ecule is disordered over two orientations with equal occupancies. In the crystal, the heterometallic mol-ecules associate via C-H⋯O inter-actions, forming supra-molecular layers with undulating topology in the ab plane. These stack along the c axis, defining voids which are occupied by the W(CO)(6) mol-ecules.