Many economic and policy decisions require balancing the well-being of individuals living today against that of individuals in the future. While behavioral economics has extensively documented that people discount future outcomes, we argue that such intertemporal trade-offs also carry an important social dimension. We design a laboratory experiment to examine altruism toward others whose participation or payment occurs in the future, and we measure perceived social distance to these individuals. Our results show that participants are more generous toward, and feel socially closer to, individuals who are present and paid today compared to those whose participation and payment is delayed by 6, 12, or 24 months. The negative effect of a later payment date is stronger than that of a later participation date, but both are significant and cumulative.