Purpose Aphasia intervention research aims to improve communication and quality of life outcomes for people with aphasia. However, few studies have evaluated the translation and implementation of evidence-based aphasia interventions to clinical practice. Treatment dosage may be difficult to translate to clinical settings, and a mismatch between dosage in research and clinical practice threatens to attenuate intervention effectiveness. The purpose of this study is to quantify a potential research-practice dosage gap in outpatient aphasia rehabilitation. Method This study utilized a two-part approach. First, we estimated clinical treatment dosage in an episode of care (i.e., treatment provided from outpatient assessment to discharge) via utilization in a regional provider in the United States. Second, we undertook a scoping review of aphasia interventions published from 2009 to 2019 to estimate the typical dosage used in the current aphasia literature. Results Outpatient clinical episodes of care included a median of 10 treatment sessions and a mean of 14.8 sessions (interquartile range: 5-20 sessions). Sessions occurred 1-2 times a week over 4-14 weeks. The median total hours of treatment was 7.5 hr (interquartile range: 3.75-15 hr). In contrast, published interventions administered a greater treatment dosage, consisting of a median of 20 hr of treatment (interquartile range: 12-30 hr) over the course of 15 sessions (interquartile range: 10-24 sessions) approximately 3 times per week. Conclusions Results demonstrate a meaningful research-practice dosage gap, particularly in total treatment hours and weekly treatment intensity. This gap highlights the potential for attenuation of effectiveness from research to outpatient settings. Future translational research should consider clinical dosage constraints and take steps to facilitate intervention implementation, particularly with regard to dosage. Conversely, health care advocacy and continued development of alternative delivery methods are necessary for the successful implementation of treatments with dosage that is incompatible with current clinical contexts. Pragmatic, implementation-focused trials are recommended to evaluate and optimize treatment effectiveness in outpatient clinical settings. Supplemental Material https://doi.org/10.23641/asha.15161568.