Men who have sex with men (MSM) account for the majority of new HIV diagnoses in the United States, including in rural areas, and MSM in rural areas face additional barriers to accessing culturally competent and appropriate HIV/STI preventive care. Multiple methods have been used to classify areas in the United States as rural, but none of these methods is specifically designed to classify areas with respect to access to culturally competent care for MSM. Using data from a large, cross-sectional study of MSM we assessed the effect of using three different methods for classifying rurality on measurements of sexual behavior and HIV/STI testing uptake. We found that the prevalence of condomless anal sex and PrEP eligibility was similar across levels of rurality regardless of the method of classification used. Across all measures of rurality, rural MSM were less likely to have tested for HIV and STIs than non-rural MSM. The disparity in HIV/STI testing persisted even in the most inclusive measure of rurality used, indicating that HIV/STI prevention studies should consider using an inclusive approach to identifying and defining rurality.