Scanning near-field and time-resolved photoluminescence spectroscopy were applied to study potential fluctuations and photoexcited carrier dynamics in single m-plane InGaN quantum well structures. The far-and near-field spectra were found to have contributions from transitions to the first and second hole levels in the extended states, and transitions in the localized states. Correlations between parameters of the near-field spectra confirmed that extended state luminescence was prevailing. The localized states, which were found to be separated from the extended states by similar to 10 meV barriers, were attributed to regions of a higher In content.