In this article, I use a Marxist feminist methodology to map the organisation of migrant sex workers' socially reproductive paid and unpaid labour in one city and country of arrival, London, UK. I argue that unfree and 'free' (sexual) labour exists on a continuum of capitalist relations of (re)production, which are gendered, racialised, and legal. It is within these relations that various actors implement, and migrant sex workers contest, unfree labour practices not limited to the most extreme forms. My analysis reveals that many migrant sex workers have very limited 'freedom'. This is in stark contrast to the classical liberal claim of sex worker rights activists and academics that the vast majority of migrant sex workers are free, and therefore not coerced, exploited or trafficked. I then consider whether the emerging labour approach to trafficking could help achieve 'freedom' for migrant sex workers. Advocates argue that anti-trafficking efforts must, and can, be refocused on extending minimum labour and social protections to all vulnerable workers. I argue that this approach is disconnected from material interests and history. Rather, migrant sex workers, sex worker rights activists, and all migrant and citizen workers and activists globally must collectively organise against 'labour unfreedom' and hence for meaningful control over their labour and lives.