Greater Buenos Aires (Gran Buenos Aires, GBA, in Spanish) is the generic denomination to refer to the urban agglomeration comprising the autonomous city of Buenos Aires and the conurbation around it, over the province of Buenos Aires—namely the adjacent 24 partidos or municipalities—which nonetheless do not constitute a single administrative unit. The conurbation spreads to the south, west and north of Buenos Aires; to the east the River Plate serves as a natural boundary.

Urban sprawl, especially between 1945 and 1980, created a vast conurbation of 9,910,282 inhabitants in the 24 conurbated partidos, as of 2010, and a total of 12,801,365 including the City of Buenos Aires, a third of the total population of Argentina.

The term "Greater Buenos Aires" is related with other expressions not necessarily well-defined: the "Buenos Aires' conurbation" (Conurbano Bonaerense), the "Greater Buenos Aires Agglomeration" (Aglomerado Gran Buenos Aires), and the "Metropolitan Area of Buenos Aires" (Área Metropolitana Buenos Aires, AMBA).