In the title compound, C(7)H(6)ClN(3)O(4)S(2)·3C(5)H(5)N, (systematic name: 6-chloro-2H-1,2,4-benzothia-diazine-7-sulfonamide 1,1-dioxide pyridine tris-olvate), chloro-thia-zide forms a 1:3 solvate with pyridine. The crystal structure is stabilized by strong inter-molecular N-H⋯N hydrogen bonds.