Purpose: Despite abundant evidence that morphemes are important in reading and spelling, little is known about the nature of processing in spelling. This study identifies multiple morphological processes over the time course of spelling, revealing that these processes are influenced by development. Method: Twenty adults and 46 children (8;0-12;1 years) completed an auditory lexical decision task followed by a spelling task, to explore the effects of morphological structure and cross-modal morphological priming by analyzing handwriting latencies before and during spelling production. Results: Adults and children both demonstrated morphological processing during lexical access -- they were faster to begin to write morphologically complex words (e.g., artist) compared to matched monomorphemic controls (e.g., article). Adults (but not children) also demonstrated cross-modal morphological priming. Further, adults (but not children) demonstrated the effects of morphological processing during spelling production. Inter-letter latencies were shorter between the last two letters of a root morpheme than the same letters in monomorphemic control words (e.g., ar[]tist compared to ar[]ticle). Conclusion: Together, these findings reflect multiple facilitative effects of morphological processing during spelling production -- during lexical access and spelling production. This highlights the need for greater integration of morphological processes into theories of skilled spelling and spelling development.