The Labour Market Impacts of Immigration to Developing Countries: Evidence from a Registration Campaign in Thailand

Little is known about the labour market impact of immigration to developing countries, because most immigration to developing countries is poorly measured. We use an unusual dataset from a campaign to register irregular migrants to study how immigration has affected wages, employment, and internal migration in Thailand. We allow for endogenous migration, whereby immigrants are disproportionately attracted to areas with higher wages. Our results suggest that immigration sufficient to increase Thailand's total labour force by one per cent would reduce Thai wages by approximately half a per cent. This effect is stronger than is generally found in developed countries. We find no evidence that immigration has reduced Thai employment rates or has affected internal migration by Thais.