Extracting the “internally waveguided” light from OLEDs, which together with losses to plasmons at the metal cathode typically account for > 50% of the light generated in the emission zone, has proven to be a particularly challenging problem. To address this problem, we fabricated devices on nano-patterned plastic substrates that disrupt the internal waveguiding. We describe thermally evaporated small molecule fluorescent and phosphorescent OLEDs fabricated on corrugated polycarbonate (PC) and polyethylene terephthalate (PET) substrates nanopatterned in a roll-to-roll process. We compare the devices fabricated on plastic/ITO to those on plastic/PEDOT:PSS and the effect of adding a µm-scale Cu honeycomb mesh to the integrated substrate/anode as well. Depending on the height and pitch of the pattern, up to a 2.5 fold increase in the outcoupling factor is observed relative to the flat substrate. Issues related to the fidelity of the conformal deposition of the various layers on the patterned plastic are also discussed, particularly the effect of the nanopatterns on device stability.