This study investigates the impact of two dimensions of Hofstede's cultural framework, namely, individualism and masculinity, on the adoption of social networking sites across countries, controlling for social-economic factors such as mobile internet penetration, a country's median age and urban population. Hierarchical regressions are conducted to test the hypothesised effects using a large-scale secondary dataset for 23 countries. Our findings reveal that both individualism and masculinity have significant impact on nations' adoption levels of social networking sites above and beyond the effects of the social-economic factors. Since little can be found in the extant literature about the influence of national culture on the use of social media, our study is among the first to provide a theoretical framework and supporting empirical evidence to establish the importance of understanding how culture impacts consumers' social networking sites adoption behaviour across countries. Limitations and implications, along with directions for future research are discussed.