Planar perovskite solar cells and modules were realized by using low temperature solution-process fabrication procedures. The photovoltaic performance was improved by optimizing a SnO2 electron transport layer and its interface with the perovskite layer. We achieved a power conversion efficiency (PCE) of 17.3% on small area cell (0.09 cm2) with negligible hysteresis and a steady-state PCE equal to 17.4%. Furthermore, shelf life tests showed a relative decrease of only 5% in PCE from its initial value after 1000 h of storage in dark conditions in air (RH 20%). Up-scaling of the technology was implemented entirely in air with fabrication of modules with a high aperture ratio of 91%. The modules delivered a maximum PCE of 13.1% obtained on an active area of 13.8 cm2 and of 11.9% on an aperture area of 15.2 cm2 representing state of art performance for fully low temperature solution processed planar perovskite solar modules. Display omitted •Low-temperature full solution process planar PSCs and PSMs.•13.1% PCE on active area (14 cm2) is obtained.•91% full laser processing aperture ratio.•Devices entirely fabricated in air (Relative humidity = 40%).•Deposition of HTL via blade coating.