The Sn(IV) atom in the title compound, [Sn(C(4)H(9))(2)Cl(2)(C(12)H(8)N(2))], is chelated by the N-heterocycle; the n-butyl groups are trans to each other whereas the Cl atoms are cis to each other. The crystal studied was a non-merohedral twin with the minor domain being in a 15.8 (1)% proportion.