Although clearcuts traditionally have been regarded as detrimental to birds associated with mature-forest, recent evidence suggests that during the post-breeding period regenerating clearcuts can provide habitat for many avian species associated with mature-forest. We examined use of regenerating clearcuts by mature-forest birds during the post-breeding period and evaluated the degree to which birds were sensitive to patch characteristics. From 15 June to 16 August in 2002–2003 we mist-netted and banded birds nine times each year in 12 regenerating hardwood clearcuts (4–7 years post-clearcut) that represented small (4.0–9.3 ha) and large (13.3–18.1 ha) clearcuts in southeast Ohio, USA. Nine nets were systematically deployed within each clearcut and placed 20, 50, and 80 m from mature-forest edges. At each net location, we measured habitat characteristics and sampled arthropod and fruit resources two-weekly. During the post-breeding period we captured 1648 mature-forest birds of 32 species, and several classic forest-interior species were among our most commonly captured species. Seventy-one percent of mature-forest captures were juveniles, which suggests that habitat provided by regenerating clearcuts may play an important role in post-fledging survival. Most post-breeding individuals avoided edges, and instead heavily used the clearcut interiors. Paradoxically, juveniles and post-breeding adults also avoided large clearcuts, and capture rates were up to four times greater in small than large regenerating clearcuts. Overall, our results suggest that regenerating clearcuts may be important resources for mature-forest birds during the post-breeding period, and forested landscapes containing a mosaic of successional stages may hold the most conservation promise for mature-forest birds.