Melting reactions of Bi₂S₃, CuX (X = Cl, Br), copper, and sulfur resulted in black needles of qua- and quinternary copper bismuth sulfide halogenides. Cu₃BiS₂Br₂ (I) has a melting point of 638(5) K and crystallizes in the orthorhombic space group Pnma with a = 804.50(6) pm, b = 393.27(3) pm, and c = 2253.2(2) pm at T = 293(2) K. Cu₄Bi₃S₅Br_3-xCl_x (x = 1.19(2)) (II) crystallizes in the monoclinic space group I2/m with lattice parameters a = 1573.7(2) pm, b = 397.52(3) pm, c = 2164.9(3) pm, and β = 95.66(1) °. Both compounds exhibit networks of thio-halogenido- bismuthate(III) polyhedra that join corners, edges, and faces. The copper(I) cations are spread over numerous contiguous trigonal or tetrahedral voids. In case of (II) a continuous pathway for copper ion transport along [010] is formed. The pseudo-potential barrier for hopping of copper ions was calculated as 30 meV only.