Digitalization has profoundly reshaped work modes and lifestyles and impacted individuals' life satisfaction. However, there has been limited research exploring this issue while comparing the effects before and during the COVID-19 pandemic. Furthermore, investigating heterogeneity across different socioeconomic groups is crucial. This study uses data from the latest three waves of the European Social Survey in 2016, 2018, and 2020 to examine the influence of Internet usage on life satisfaction, unravel its underlying mechanisms, and conduct heterogeneity analysis with the fixed-effects ordered logit model and propensity score matching method. The empirical findings reveal the following: (a) Internet usage has significant and positive effects on life satisfaction, although the marginal effects of Internet usage decreases as respondents' life satisfaction increases; (b) respondents with a "right" political tendency, higher levels of social interaction and trust, females, older individuals, higher income earners, those with lower education levels, better health conditions, and stronger religious beliefs tend to report higher life satisfaction; (c) work flexibility, work-life balance, and team engagement are identified as essential mediating factors in the relationship between Internet usage and life satisfaction; (d) Internet usage has had a significant and positive effect on life satisfaction since the outbreak of the COVID-19 pandemic, whereas this was not the case before the pandemic; and (e) the influence of Internet usage on life satisfaction is more pronounced among young, affluent communities, well-educated individuals, Eastern and Central Europeans, non-managers, and employees of central/local governments and private firms. This study underscores the rapid socioeconomic transformation induced by digitalization in Europe and provides valuable insights on leveraging the Internet to improve individual life satisfaction in the post-pandemic era. Thank you for your insightful comments and suggested revisions. With your guidance, we are now submitting a revised version of our paper by adding Section 5.5 to propose the lessons learned from the COVID-19 experience. Four related papers from SocioEconomic Planning Sciences are also cited at where appropriate. All modifications are highlighted in red for easy reference. Below are our point-by-point responses to your feedback. Reviewer #1: The authors improved the manuscript in accordance with my previous comments. My main concern is with the data used for the analysis. I suggest the authors emphasise what lessons could be learned from the COVID experience. This part could be included in the discussions and conclusions. Perhaps the authors should also emphasise this in the title. A: Thank you for your comment. The dataset used in this study was obtained from the ESS, which has been widely used in academic researches, include the studies of Palermo et al. (2022) and Tubadji & Nijkamp (2017) that published on SocioEconomic Planning Sciences. We estimated the relationship between Internet usage and life satisfaction by using the latest three waves of ESS, namely rounds 8, 9, and 10. Since Round 10 contains information on people's Internet usage during the pandemic, we therefore in a good position to compare the impact of Internet usage on life satisfaction before and during the COVID-19 pandemic. Thank you for your suggestion, in the new version we added Section 5.5 to the Response to Reviewers 2 Discussion section to propose the lessons learned from the COVID-19, please review. Besides, we prefer to remain current title because the lessons are derived from the relationship test and heterogeneity analysis, which are illustrated in the title. Ref: [1] Palermo F, Sergi BS, Sironi E. Does urbanization matter? Diverging attitudes toward migrants and Europe's decision-making. Socio-Econ Plan Sci. 2022;83. https://doi.org/10.1016/J.SEPS.2022.101278. [2] Tubadji A, Nijkamp P. Green Online vs Green Offline preferences on local public goods trade-offs and house prices. Socio-Econ Plan Sci. 2017;58, 72-86. https://doi.org/10.1016/J.SEPS.2016.11.001. Reviewer #2: After reviewing the authors' responses, extensions and improvements to my initial assessments, my opinion is that the article has clearly improved in robustness and that it is publishable in its current format. A: Thank you for your nice words. It is with your suggestion that the quality of this article got improved. Highlights Ordered logit model, PSM and IV method are used to analyze Internet-satisfaction nexus in Europe. Internet usage can improve life satisfaction during COVID-19, but it is not the case before the pandemic. Work flexibility, work-life balance, and team engagement plays a mediating role in Internet-satisfaction nexus. Heterogeneity analyses in terms of age, income, region, education, and occupation have been made. Highlights 1 How did Internet usage affect life satisfaction before and during COVID-19? 1 Mediating effects and heterogeneity analysis 2 3 Abstract: Digitalization has profoundly reshaped work modes and lifestyles and impacted individuals' 4 life satisfaction. However, there has been limited research exploring this issue while comparing the 5 effects before and during the COVID-19 pandemic. Furthermore, investigating heterogeneity across 6 different socioeconomic groups is crucial. This study uses data from the latest three waves of the 7 European Social Survey in 2016, 2018, and 2020 to examine the influence of Internet usage on life 8 satisfaction, unravel its underlying mechanisms, and conduct heterogeneity analysis with the fixed-9 effects ordered logit model and propensity score matching method. The empirical findings reveal the 10 following: (a) Internet usage has significant and positive effects on life satisfaction, although the 11 marginal effects of Internet usage decreases as respondents' life satisfaction increases; (b) respondents 12 with a "right" political tendency, higher levels of social interaction and trust, females, older individuals, 13 higher income earners, those with lower education levels, better health conditions, and stronger 14 religious beliefs tend to report higher life satisfaction; (c) work flexibility, work-life balance, and team 15 engagement are identified as essential mediating factors in the relationship between Internet usage and 16 life satisfaction; (d) Internet usage has had a significant and positive effect on life satisfaction since