Salt marshes have a long history of tidal restriction, resulting in marsh compaction, subsidence, reduced tidal range, and invasion of nonnative species that impair nekton support functions. At Cape Cod National Seashore, the availability of high-quality, long-term monitoring data provides an opportunity to evaluate factors that drive restoration success of biological communities in marsh ecosystems undergoing gradients of restoration. In the restored marsh at Hatches Harbor (“HHR”), 67.5 % of the variability in nekton community composition (“NCC”) was due to a temporal trend, due to large abundances of Fundulus heteroclitus that changed to Crangon septemspinosa and Carcinus maenas in the later years. The paired unrestricted marsh (“HHUR”) also showed a temporal trend, with 57.6 % of the variability attributed to a change from F. heteroclitus to C. septemspinosa. At the partially restored Moon Pond (“MP”) site, NCC was only moderately influenced by a temporal trend (30.1 %), with samples in early years dominated by Palaemonetes spp. and F. heteroclitus shifting to C. septemspinosa, Menidia spp., and C. maenas. Water quality (6.1 %) and sample timing (10.3 %) were also important drivers of NCC at MP. The unrestricted Nauset Marsh showed a weak temporal trend (49.5 %) with samples in early years dominated by C. septemspinosa, whereas F. heteroclitus and C. maenas drove NCC patterns in the later years. The nekton community in the Hatches Harbor marsh has converged over time, but NCC at the partially restored MP site is still changing due to hydrologic restoration.