Guidelines recommend maximal antianginal medical therapy before attempted coronary artery chronic total occlusion (CTO) percutaneous coronary intervention (PCI). The degree to which this occurs in contemporary practice is unknown. We aimed to characterize the frequency and variability of preprocedural use of antianginal therapy and stress testing within 3 months before PCI of CTO (CTO PCI) across a nationally integrated health care system. We identified patients who underwent attempted CTO PCI from January 2012 to September 2018 within the Veterans Affairs Healthcare System. Patients were categorized by management before CTO PCI: presence of ≥2 antianginals, stress testing, and ≥2 antianginals and stress testing within 3 months of PCI attempt. Multivariable logistic regression and inverse propensity weighting were used for adjustment before trimming, with median odds ratios calculated for variability estimates. Among 4250 patients undergoing attempted CTO PCI, 40% received ≥2 antianginal medications and 24% underwent preprocedural stress testing. The odds of antianginal therapy with more than one medication before CTO PCI did not change over the years of the study (odds ratio [OR], 1.0 [95% CI, 0.97-1.04]), whereas the odds of undergoing preprocedural stress testing decreased (OR, 0.97 [95% CI, 0.93-0.99]), and the odds of antianginal therapy with ≥2 antianginals and stress testing did not change (OR, 0.98 [95% CI, 0.93-1.04]). Median odds ratios (MOR) showed substantial variability in antianginal therapy across hospital sites (MOR, 1.3 [95% CI, 1.26-1.42]) and operators (MOR, 1.35 [95% CI, 1.26-1.63]). Similarly, preprocedural stress testing varied significantly by site (MOR, 1.68 [95% CI, 1.58-1.81]) and operator (MOR, 1.80 [95% CI, 1.56-2.38]). Just under half of patients received guideline-recommended management before CTO PCI, with significant site and operator variability. These findings suggest an opportunity to reduce variability in management before CTO PCI.