Abstract
In the title compound, C(18)H(15)OP.C(7)H(5)ClO(2), the triphenylphosphine oxide molecule forms a single directed hydrogen bond with the 3-chlorobenzoic acid molecule, with an O.O=P distance of 2.607 (2) A. The C-Cl and C=O bonds adopt a cisoid conformation in the 3-chlorobenzoic acid molecule.