Chinese networks are known to act as trade catalysts by enforcing contracts and providing market information. This paper shows they also play a role in import-tariff evasion. As illegal trade activities occur outside the law, market information is scant and formal contract enforcement institutions are non-existent. This renders networks the more important for the matching of illicit-minded traders, identification of corrupt customs agents and enforcement of informal contracts. In this paper, we find robust evidence that Chinese networks, proxied by ethnic Chinese migrant populations, increase tariff evasion, that is, the tariff semi-elasticity of China’s missing trade.