The reaction of the arylphosphonic acid esters 4,4′-[(i-PrO) 2 P(O)]C 6 H 4 C 6 H 4 [P(O)(Oi-Pr) 2 ] (L 1 ), 1,3,5-[(i-Pr O) 2 P(O)] 3 C 6 H 3 (L 2 ), and 5-t-Bu-1,3-[(i-PrO) 2 P(O)] 2 C 6 H 3 (L 3 ), respectively, with bismuth halides BiX 3 (X = Cl, Br, I) gave seven novel bismuth coordination polymers that have been characterized by single-crystal X-ray diffraction analysis. The solid-state structures of [(BiCl 3 )(L 1 )] (1), [(BiBr 3 ) (L 1 )]·0.25CH 3 CN (2·0.25CH 3 CN), [(BiI 3 ) 2 (L 1 )]·0.25CH 3 CN (3·0.25CH 3 CN), [(BiCl 3 )(L 2 )] (4), [(BiCl 3 ) 2 (L 2 )] (5), [(BiBr 3 ) 2 (L 2 )]·CH 3 CN (6·CH 3 CN), and [(BiCl 3 )(L 3 )] (7) are presented. Thermal analysis of [(BiCl 3 ) 2 (L 2 )] (5) is indicative of a conversion of the complexes into a bismuth phosphonate by complete i-PrX elimination, whereas for [(BiBr 3 ) 2 (L 2 )] (6), elimination of i-PrBr and BiBr 3 is assumed. Compounds 1-3 form one-dimensional coordination polymers, whereas twodimensional networks are observed for compounds 4-7.