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The Eastern Alps were affected by a profound post‐collisional tectonic reorganisation in Neogene time, featuring indentation by the Adriatic upper plate, rapid uplift and filling of the eastern Molasse Basin, exhumation and eastward orogen‐parallel transport of Paleogene metamorphic units in the orogenic core, and a shift from northward thrust propagation in the European plate to southward propagation in the Adriatic plate. We test the idea that these events were triggered by slab detachment by reconstructing the indentation process. This involves sequentially restoring N‐S and E‐W cross‐sections of the orogenic wedge and correcting for out‐of‐section orogen‐parallel transport with a map‐view reconstruction. We propose two phases of indentation: Initially (23 and 14 Ma), the whole Adriatic crust acted as an indenter. Its northward motion was accommodated by upright folding and orogen‐parallel extensional exhumation in the Tauern Window. This phase was followed (14 Ma to Present) by continued orogen‐parallel transport of the orogenic wedge into the Pannonian Basin and deformation of the leading edge of the Adriatic indenter, forming the Southern Alps fold‐thrust belt. The lower crust of the Southern Alps indented the base of the Venediger Nappes in the Tauern Window, forming a high‐velocity (6.8–7.25 km/s) ridge in map view at 30–45 km depth. By correlating the post‐23 Ma orogenic evolution with presently imaged European slab segments in P‐wave teleseismic tomography, we discern two possible Neogene slab removal events: One from 23 to 19 Ma triggering tectonic reorganisation of the Eastern Alps and its foreland basin, and potentially a second event after 14 Ma. The Eastern Alps were first indented by Adriatic lithosphere (23 and 14 Ma), then by Adriatic lower crust as the indenter deformed (14 and 0 Ma)Shortening of the orogenic wedge since 23 Ma requires 135 km of subduction and 90 km of eastward extrusion of orogenic lithosphereSlab detachment at 23 and 20 Ma and possibly after 14 Ma is constrained by areal balancing of crust and mantle The Eastern Alps were first indented by Adriatic lithosphere (23 and 14 Ma), then by Adriatic lower crust as the indenter deformed (14 and 0 Ma) Shortening of the orogenic wedge since 23 Ma requires 135 km of subduction and 90 km of eastward extrusion of orogenic lithosphere Slab detachment at 23 and 20 Ma and possibly after 14 Ma is constrained by areal balancing of crust and mantle