Encouraging sustainable water use is a critical endeavor in addressing issues associated with short- and long-term droughts. Toilets account for up to 26.7% of indoor household water use. Therefore substantial opportunity exists to conserve water via reduced flushing after urination at home. Here, we use an online survey (N = 1008) to identify barriers to reduced flushing. The majority of participants reported they always flush (63%) and believed that others should always flush. Social norms surrounding cleanliness are the most prevalent reasons for flushing. Results suggest four main barriers to reducing flushing: disgust sensitivity, habitual nature of flushing, norms regarding cleanliness, and lack of pro-environmental motivations. Participants who always flush are less likely to sacrifice for the environment than occasional flushers. Participants tended to underestimate average American water use and their own water use. Targeted interventions to decrease urine-related disgust and increase pro-environmental motivations may help achieve water conservation goals.