introductionTeledermatology has emerged as an important strategy to enhance access to high-quality skin care. METHODS AND ANALYSIS: The study is a prospective, stepped-wedge cluster randomised trial with cross-sectional exposure and outcome measurement via retrospective database analysis of administrative records. Each cluster is a VHA facility deemed eligible for the trial. We assign the intervention using a cluster-level balanced randomisation scheme based on facility size, baseline teledermatology uptake and geographic location. The trial will test whether patients receiving dermatological care at participating facilities will have better access compared with patients receiving care through the current standard process. The primary outcomes proxy for patient-level access to dermatology services, including (1) consult completion time for teledermatology consults; (2) appointment completion time for new dermatology consults; and (3) travel distance for dermatology services. As secondary outcomes, we will assess facility-level adoption outcomes, that is, the number of dermatology encounters and the proportion of teledermatology consults out of all dermatology encounters. To account for secular trends in outcomes and for correlation across individuals within clusters, we will assess the impact of the intervention using generalised linear mixed regression models. DISCUSSION: Streamlining the current practice for store-and-forward teledermatology in the VHA can improve access to expert dermatological care for US veterans. The lessons learnt in this trial could validate the use of mobile technology for consultative store-and-forward dermatology in a large healthcare organisation. The results may also be of interest to other medical specialties assessing the merits of implementing mobile telehealth. PROTOCOL VERSION: Version 3; 7 November 2018. TRIAL REGISTRATION NUMBER: NCT03241589; Pre-results.