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Abstract Vairimorpha (=Nosema) ceranaeis a widespread pollinator parasite that commonly infects honeybees and wild pollinators, including bumblebees. Honeybees are highly competentV. ceranaehosts and previous work in experimental flight cages suggestsV. ceranaecan be transmitted during visitation to shared flowers. However, the relationship between floral visitation in the natural environment and the prevalence ofV. ceranaeamong multiple bee species has not been explored. Here, we analyzed the number and duration of pollinator visits to particular components of squash flowers—including the petals, stamen, and nectary—at six farms in southeastern Michigan, USA. We also determined the prevalence ofV. ceranaein honeybees and bumblebees at each site. Our results showed that more honeybee flower contacts and longer duration of contacts with pollen and nectar were linked with greaterV. ceranaeprevalence in bumblebees. Honeybee visitation patterns appear to have a disproportionately large impact onV. ceranaeprevalence in bumblebees even though honeybees are not the most frequent flower visitors. Floral visitation by squash bees or other pollinators was not linked withV. ceranaeprevalence in bumblebees. Further,V. ceranaeprevalence in honeybees was unaffected by floral visitation behaviors by any pollinator species. These results suggest that honeybee visitation behaviors on shared floral resources may be an important contributor to increasedV. ceranaespillover to bumblebees in the field. Understanding howV. ceranaeprevalence is influenced by pollinator behavior in the shared floral landscape is critical for reducing parasite spillover into declining wild bee populations.