Title: The moderating role of ICT diffusion in informal economy-pollution nexus in KSA

This study examines the moderating ICT plays in shadow economy–environmental pollution nexus in Nigeria between 1984 and 2017. Further, the study also determines the threshold level of ICT that lessens shadow economy and abates environmental pollution. Results from the study show that shadow economy has a positive and significant effect on environmental pollution both in the short and long run, while ICT has a negative effect on environmental pollution. This reveals that shadow economy worsens environmental quality while ICT abates environmental pollution. The interactive term of shadow economy with ICT has a negative but insignificant effect on environmental pollution in the long run. It implies that ICT is weak to bring about significant reduction in shadow economy and environmental pollution. Further, the threshold level of ICT required to lessen the effect of shadow economy and abate environmental pollution is found to be 5.69 on an ordinal scale of 0–10