The aim of the present study was to investigate developmental changes in encoding processes between 6‐year‐old children and adults using event‐related potentials (ERPs). Although episodic memory (‘EM’) effects have been reported in both children and adults at retrieval and subsequent memory effects have been established in adults, no previous ERP studies have examined subsequent memory effects in children. This represents a critical gap in the literature because encoding processes, and changes in neural correlates supporting encoding, partially account for age‐related improvements in children's memory performance. Results revealed that subsequent memory effects differed between children and adults temporally, directionally, and topographically. These findings lend support to the hypothesis that encoding processes and their neural correlates are an important source of change in memory development. A video abstract of this article can be viewed at http://youtu.be/sH83_qVimgc. The aim of the present study was to investigate developmental changes in encoding processes between 6‐year‐old children and adults using event‐related potentials (ERPs). Although episodic memory (‘EM’) effects have been reported in both children and adults at retrieval and subsequent memory effects have been established in adults, no previous ERP studies have examined subsequent memory effects in children. This represents a critical gap in the literature because encoding processes, and changes in neural correlates supporting encoding, partially account for age‐related improvements in children's memory performance.