INTRODUCTION: Access to care (ATC) is an important component of providing quality healthcare. Clinics need to be able to accurately measure access; however, patients' reports of access may be different from performance-based data gathered using administrative measures. The purpose of this research is to examine the relationship between ATC administrative data and patient survey results. MATERIALS AND METHODS: This is a retrospective study performed in military medical treatment facilities. Survey data were obtained from the Joint Outpatient Experience Survey (JOES), and administrative data were collected from the Military Health System Data Repository. The data period was from May 2016 through March 2017 for 135 parent Military Treatment Facilities. This study was approved under the Defense Health Agency Internal Review Board (IRB number: CDO-15-2025). The analyses compare JOES ATC measures to administrative ATC measures. Overall correlation analyses and multivariate regression analyses were performed in order to generate observable correlations between access and healthcare measures (both administrative measures and patient survey items). RESULTS: Results show moderate correlations between the facilities' ATC survey items and administrative measures. These correlations were affected by the composition of the facility patient mix. The patient-based ATC measures from the JOES survey are related to administrative ATC measures collected and monitored by the facilities. In each final regression model, the coefficients for the ATC administrative variables were significant and negative which indicates that as the wait time for an appointment increases, patients' ratings of the time between scheduling and appointment dates declines and patients' assessments of being able to see a provider declines as well. CONCLUSIONS: Measuring ATC is a vital step in ensuring the health of patients and the provision of high quality care. Both patient surveys and administrative data are widely used for measuring ATC. This study found statistically significant moderate associations between survey and administrative ATC measures, which remained significant even after controlling for patient characteristics of the facilities. These study results suggest that administrative data can provide an accurate assessment of access; however, survey items can be useful for diagnosing potential issues with access, such as call center scheduling and provider availability. Future studies should explore the gaps in research surrounding best practices at facilities which have high patient experience with access, and look at other survey measures related to access, such as telephone resources and web-based communication programs.