How is it that migrants, among the most highly controlled groups of the population, provide such de-regulated labour? This paper argues that rather than a tap regulating entry, immigration controls are a mould constructing certain types of workers through the requirements and conditions of immigration status. In particular state enforced immigration controls, themselves a response to global mobility, give employers greater control over labour mobility. Migrants both manipulate and are constrained by immigration status. An analysis of migration and labour markets must consider matters of time: length of period in a job; the impact of working time on retention, length of stay, changing immigration status etc. Attention to these temporal dimensions is particularly important in theorizing the relation between immigration status and precarious work.