A buffered stacking apparatus selectively diverts horizontally disposed documents from a main conveying path, then stacks and transports the documents to replaceable receiving receptacles. The apparatus has a primary horizontal conveyor belt with a lower reach defining a horizontal primary conveying path and at least one secondary conveyor belt having an upper reach which, when the secondary conveyor belt is in a horizontal position, is disposed in a lower juxtaposed relation to the lower reach of the primary conveying belt. The buffered stacking system also selectively effects pivotal movement of the secondary conveyor belt from the horizontal position to a second inclined position wherein the reach of the secondary belt is inclined to the lower reach of the primary conveyor belt. Documents being transported along the primary conveying path are diverted along the inclined reach when the secondary conveying belt is inclined. The documents diverted at the selected diverter station are transported by the inclined reach to a corresponding buffer assembly which horizontally stacks and aligns the documents. The buffer assembly includes a sweeping device which engages and selectively sweeps the stacked documents from the buffer assembly to the corresponding receiving receptacle disposed transversely adjacent the buffer assembly.