A new near-infrared switchable electrochromic polymer containing carbazole pendant (poly-SNSC), synthesized by electrochemical polymerization of 2,5-bis-dithienyl-1H-pyrrole (SNS) main chain, has been prepared. The electrochemical and optical properties of SNSC monomer and its polymer have been investigated. Because of having two different electro-donor moieties; that is, carbazole and SNS, SNSC gave two separate electrochemical oxidation and also light brown color of the film in the neutral state turn into gray on oxidation. An electrochromic device, contructed in the sandwich configuration [indium tin oxide (ITO)-coated glass/anodically coloring polymer (poly-SNSC)//gel electrolyte//cathodically coloring polymer (PEDOT)/ITO-coated glass] and exhibited a high coloration efficiency (1216 cm(2) C-1), a very short response time (about 0.3 s), low driving voltage, and a high redox stability. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4419-4427, 2010