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The partitioning of fluvial sediment load across continental margins is an important control on strata formation and sequence development; however, few quantitative sediment budgets that encompass entire dispersal systems exist. For the Ganges-Brahmaputra river system, sediment discharge is estimated to be 10⁹ t/yr at gauging stations ∼300 km inland of the coast, but little has been known of the downstream fate of this material. Geochronological, geophysical, and stratigraphic investigations of the lowland flood plain, delta plain, and shelf help to delineate the extent of Holocene fill and allow calculation of a first-order sediment budget. Results reveal that 1500 × 10⁹ m³ of sediment fill has been sequestered within the flood plain and delta plain since ca. 7000 yr B.P., or about one-third of the annual discharge. The remaining load appears to be apportioned between the prograding subaqueous delta (1970 …