Responsiveness has emerged as a new dimension of differentiation as e-commerce continues to evolve. However, the pursuit of rapid service is not without limits. An obvious consequence is higher costs, and a second but less considered one is higher carbon emissions. Against this backdrop, our research investigates service time and price decisions for an e-tailer. A holistic social welfare perspective that accounts for the e-tailer's profit, consumer surplus as well as the environmental impact of carbon emissions is adopted. Equilibrium service time and price are derived for certain operational settings. In view of the complex interplay between service strategies and carbon emissions, we propose the carbon compensation index that measures the degree of recovery from the environmental impact through carbon tax in monetary terms. The optimal service strategies under different regulatory and market environments are illustrated. Further, our results reveal that excessive taxation could be detrimental to overall social welfare.