Historians have documented rising farm sizes throughout the period 1450–1850. Existing studies have revealed much about the mechanisms underlying the development of agrarian capitalism. However, we currently lack any consensus as to when the critical developments occurred. This is largely due to the absence of sufficiently large and geographically wide-ranging datasets but is also attributable to conceptual weaknesses in much of the literature. This article develops a new approach to the problem and argues that agrarian capitalism was dominant in southern and eastern England by 1700 but that in northern England the critical developments came later.