The emergence of the Triple Alliance empire and the consolidation of political power in the Basin of Mexico is traditionally associated with a high level of economic integration achieved through regional market exchange. Although researchers debate whether the market system was dominated by commercial factors or political forces, the assumption that the pax azteca led to a single, basin-wide exchange system is not generally challenged. Yet an increasing number of stylistic and compositional analyses indicate that significant regional subdivisions existed within the Aztec core, although the spatial scale, nature, and significance of these systems remains poorly understood. This study contributes to the body of evidence suggesting that economic divisions existed under the Triple Alliance, by presenting spatial patterning in Aztec Red Wares (guinda or rojo pulido) ceramics. By combining both stylistic and compositional analyses of this ceramic ware, it is possible to demonstrate both the strength of economic divisions as well as map their boundaries for a significant portion of the Basin. The regional patterns in artifact distribution highlighted in this and prior studies underscore the complexity of exchange interactions that evolved under Aztec rule and which must be explained by future models of the Aztec market system.