It is generally agreed in social scientific scholarship that federal institutions promote efficiency and economic growth in the modern world. This chapter asks whether the same case can be made for antiquity. Political scientists and economists recognize three major mechanisms by which federal institutions promote economic growth: decentralized fiscal decision-making that incentivizes the adoption of policies enhancing local economies; high redistributive capacity that can direct resources where they are most needed; and reliance on local revenues that encourages local governments to invest in public goods that enhance market activity. Although there is some evidence to suggest that these each of these institutional arrangements existed in antiquity, it is argued that there is simply not enough evidence to demonstrate that they did, in fact, lead to economic growth in the ways that the modern theory of fiscal federalism predicts. The chapter then explores several different ways in which federal institutions may have led to economic growth in the case of Greek antiquity – regional property rights and the pooling of complementary resources, shared currency, and enhanced diplomatic power – while cautioning that there is no evidence to prove that there was a causal link between any of these practices and actual economic growth.