Capitalist commodities have a necessary but overlooked accompaniment: aftermarkets. Aftermarkets are conventionally understood as secondary commercial transactions linked to commodity consumption and circulation. Yet for many products with accelerating design complexity, tighter regulation, growing debt financing, safety, and sustainability concerns, the action is in aftermarkets. Following feminist economic geography’s recognition of betweenness and messiness, we theorize commodities and their aftermarkets beyond the production-consumption binary. Three themes emerge. First, purchased commodities are far from finished. Commodification remains ongoing after exchange, with actors tussling over value extraction. Second, beyond transactional conceptions, aftermarkets are the loci of ongoing social relations, especially for products essential to life opportunities. Manufacturers manipulate time horizons, locking consumers into relationships while encouraging subsequent sales and preconfiguring second-hand aftermarkets. Third, commodities are imbricated in multidirectional power geometries, embodying informational, technological, financial, and labor relations that evolve in everyday circulation, use, decay, and waste. We illustrate via automobiles and their aftermarkets, visiting spaces at the production-consumption interface. Cars are increasingly embedded with digital technologies and noninterchangeable components, enabling firms to coordinate aftermarkets, marginalize independent operators, harvest driver information, and predict profits. Meanwhile, car dependencies among vulnerable households are exploited. Inequalities and conflicts unfurl between competing capitalist interests, regulators, and households across the income spectrum. Mediating social relations are predatory finance, calculative designs, data platforms, and technological rents. Commodities, we conclude, are unfinished. Aftermarkets must figure more prominently in economic geography, as important arenas of value creation suffused with uneven social relations.