As cross-country comparisons of education systems have become increasingly important for policy-making, different structural arrangements have attracted attention in the pursuit of equity and excellence. One area of interest has been instructional time in formal schooling. Missing in such comparisons is the role instruction outside of formal/compulsory schooling. Supplementary education in its many forms has a long history, global reach, and is increasingly attracting scholarly attention. Asia is a notable location and particularly China, where there has been rapid expansion, intensification, and visibility. In this paper, we mobilise Eacott’s relational approach to argue that supplementary education, at least in the highly competitive urban centres, is no longer supplementary and that orthodox approaches to understanding it based on a perceived separation from compulsory education cannot adequately describe the contemporary condition. Our argument is that orthodox approaches conceive of the problem of supplementary education as one of access. We seek to unsettle orthodoxy by re-casting supplementary education as not supplementary at all and instead.