This article explores how the legal system has constructed, over time, the concept of the “wage”. Drawing on insights from classical political economy it contrasts a conception of the wage as the cost of social reproduction (a “social wage”), with the neoclassical notion of the wage as the price of a commodity (a “market wage”) that we see embedded in legal and political discourse today. Drawing on historical sources, it explores how these competing ideas of the wage have been reconstructed in juridical language in case law and legislation over time, exploring at the same time the impact of this process on the relationship between minimum wages and tax credits. This analysis is then used to shed light on the conception of the wage embedded in the National Minimum Wage Act 1998, providing a critical re-evaluation of the “National Living Wage” introduced in 2016.