•Pro-environmental behaviours (PEBs) are less well understood in developing countries.•Innovativeness was found to have the greatest positive effect on consumers’ intentions.•Materialism was found to have a significant negative effect on consumers’ intentions.•No significant effect was found for social influence on consumers’ intentions.•Consumers’ intentions were found to have a greater effect on indirect-PEBs than direct-PEBs. Major environmental issues facing our planet are considered to be partly rooted in consumer overconsumption that has resulted from high economic growth. Pro-environmental behaviours (PEBs) have been studied extensively in developed Western countries but more research is needed in developing non-Western countries. Additionally, there are increasing calls for research providing broader theoretical and behavioural explanations of consumers’ intentions to adopt PEBs. Therefore, the aim of this research was to examine the factors affecting consumers’ PEBs in Saudi Arabia. Quantitative data (n = 613) were collected using a survey method. The proposed conceptual model and associated hypotheses were tested using structural equation modelling. The results revealed that consumers’ intentions to adopt direct- and indirect-PEBs are affected by innovativeness, materialism, perceived consumer effectiveness, and environmental concern, but not by social influence. Evidence was also found of differences between younger and older respondents. These findings can be used to formulate effective marketing strategies to benefit the environment, society, and sustainable companies in the country.