In the title complex, [Co(C(6)H(14)NO(3))(N(3))] or [Co(teaH(2))N(3)], the Co(II) atom resides in a trigonal-bipymidal O(3)N(2) environment formed by three O atoms and one N atom from a simply deprotonated tetra-dentate triethano-lamine ligand, and one N atom from an azide ligand. The O atoms define the equatorial plane whereas both N atoms are in axial positions. The mononuclear units are linked through O-H⋯O hydrogen-bonding inter-actions between the ethanol OH groups and the ethano-late O atom of a neighbouring complex into chains running parallel to [010].