In the title compound, C20H15ClIN3O3, the dihedral angle between the quinazolinone ring system [r.m.s. deviation = 0.047 (2) Å] and the pendant benzene ring is 82.63 (11)°. The mol-ecular conformation is stabilized by intra-molecular C-H⋯O inter-actions. In the crystal, the mol-ecules are linked by N-H⋯O hydrogen bonds into chains along the a-axis direction. Another set of chains propagating along [101] is formed due to inter-molecular I⋯Cl short contacts of 3.427 (1) Å, thus giving layers parallel to (010). The layers are connected by C-H⋯π and π-π inter-actions, the shortest distance between the centroids of aromatic rings being 3.8143 (16) Å.