Solitude is a rising phenomenon in the western world. The share of people affected by solitude has been rising for some time and the Covid-19 pandemic has further brought this trend to the fore. Yet, we know next to nothing about the aggregate subnational economic impact of the rise in solitude. In this paper, we analyse the consequences of solitude on regional economic performance across Europe, distinguishing between two of its key dimensions: alone living, proxied by the regional share of single-person households and loneliness, proxied by the aggregate share of social interactions. We find that solitude has important implications for economic development, but that these go in different directions. While alone living is a substantial driver of economic growth across European regions, high shares of lonely people undermine it. The connection of loneliness with economic growth is, however, dependent on the frequency of in-person meetings, with large shares of the population meeting others socially on a weekly basis, alongside a small percentage of people who never meet others, yielding the best economic returns.