In the title compound, C(16)H(13)BrFN(3)O(2)S, the dihedral angle between the aromatic rings is 2.55 (19)° and the C=N-N=C torsion angle is 178.9 (3)°. The conformation of the thia-zine ring is an envelope, with the S atom displaced by -0.811 (3) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.042 Å). In the crystal, C-H⋯O inter-actions link the mol-ecules and weak aromatic π-π stacking between the fluoro-benzene and bromo-benzene rings [centroid-centroid separation = 3.720 (2) Å and inter-planar angle = 2.6 (2)°] is also observed.