(Figure Presented) A polytriarylamine-based oligomer is reported as a hole transporting material and its application in solid-state CH3NH3PbI3 based heterojunction solar cells is described. It yields a power conversion efficiency of 12.0% under 99.6 mW cm-2 illumination. In addition to suitable energy levels and high hole mobility, the low preparation cost makes it a promising candidate for photovoltaics. © 2014 Wiley-VCH Verlag GmbH & Co. KYWGaA.