We performed constant voltage stresses with different bias conditions on all-organic complementary inverters. We found a 20% maximum variation of DC inverter parameters after a 10(4)-s stress. However, the largest stress-induced degradation was found in the delay times, which increased by a factor as high as 7. This is mainly due to the threshold voltage variation of the p-type thin-film-transistor and the mobility reduction of the n-type thin-film transistors, which both decrease the saturation drain current. (C) 2015 Elsevier Ltd. All rights reserved.