Students in K-12 settings experience poor writing outcomes, with less than 30% of students writing at the proficient level. Coupled with the pressure to improve academic outcomes with limited resources, schools are in dire need of efficient, universally provided instructional activities that promote writing skills. Performance feedback on writing fluency was designed to be a brief, low-resource universally provided instructional activity to facilitate writing development and has demonstrated moderate to large effects on formative writing measures. The current study was conducted to directly evaluate the extent to which performance feedback on writing fluency is cost-effective. This study uses the ingredients method to estimate the costs of providing performance feedback on writing fluency and calculates incremental cost-effectiveness ratios based on secondary data from a randomized controlled trial. Results suggest that performance feedback is more cost-effective than comprehensive systems reform initiatives and comparable to other universally provided interventions, and therefore should be considered a cost-effective approach to improve writing fluency for all students. Results provide school psychologists with concrete examples of how to support prevention and intervention activities aimed to improve student writing outcomes. Limitations and suggestions for future research are also discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).