When people can self-insure via migration, they may have less need for informal risk sharing. At the same time, informal insurance may reduce the need to migrate. To understand the joint determination of migration and risk sharing, I study a dynamic model of risk sharing with limited commitment frictions and endogenous temporary migration. First, I characterize the model. Second, I structurally estimate the model using the new ICRISAT panel from rural India. Third, I introduce a rural employment scheme. The policy reduces migration and decreases risk sharing, lowering the welfare gain of the policy.

We estimate the aggregate productivity gains from reducing barriers to internal labor migration in Indonesia, accounting for worker selection and spatial differences in human capital. We distinguish between movement costs, which mean workers will move only if they expect higher wages, and amenity differences, which mean some locations must pay more to attract workers. We find modest but important aggregate impacts. We estimate a 22 percent increase in labor productivity from removing all barriers. Reducing migration costs to the US level, a high-mobility benchmark, leads to a 7.1 percent productivity boost. These figures hide substantial heterogeneity. The origin population that benefits most sees a 104 percent increase in average earnings from a complete barrier removal, or a 25 percent gain from moving to the US benchmark.

We document that an experimental intervention offering transport subsidies for poor rural households to migrate seasonally in Bangladesh improved risk sharing. A theoretical model of endogenous migration and risk sharing shows that the effect of subsidizing migration depends on the underlying economic environment. If migration is risky, a temporary subsidy can induce an improvement in risk sharing and enable profitable migration. We estimate the model and find that the migration experiment increased welfare by 12.9%. Counterfactual analysis suggests that a permanent, rather than temporary, decline in migration costs in the same environment would result in a reduction in risk sharing.