This paper investigates the determinants of the productivity of independent retail stores in Sweden by focusing on the impact of market size and regional hierarchy while controlling for several store and employee characteristics over time. The analysis utilizes Swedish store-level data for the years 2002-2008. To capture the urban-periphery interaction in retail markets, the analysis (i) uses an accessible market potential measure, which captures the impact of the potential demand both in close proximity in the region, and from outside the region separately, and (ii) investigates the stores that are located in central and non-central markets respectively. The results show an approximately 10 percent higher productivity premium associated with the market size in close proximity for centrally located independent stores, whereas regional market size is found to play an equally important role for both stores located in central markets and stores located in peripheral markets. The findings also show that employee characteristics do not contribute to the productivity of stores in central markets but that small but significant productivity returns are captured for stores located in peripheral markets. The differences in the impact arising from the market potential measures highlight the importance of taking the spatial continuum and regional hierarchy into account in an examination of the market size-productivity relationship for retailers.