Point-of-use water filters are a means to provide clean water vital to the health of people in developing countries. The factors that influence the adoption of this technology include hygiene knowledge, health beliefs related to the use of new technology, and technical issues with using the filter (e.g., water taste and breakage). This study examines how people in Mayan communities in rural Guatemala perceived biosand filters they had received and what factors related to their filter use. Based on the survey and interviewer observations, approximately 53% were regular filter users, 28% were irregular filter users, and 19.4% were non-filter users. The observational data revealed that actual filter use is lower than self-reported use, reflecting complexities in the adoption of technology. One such complexity can be seen in the connection between health beliefs and behavior. The belief that believing drinking filtered water is salubrious does not necessarily coincide with filter use, but education and hygienic practices correlated with regular filter use. Furthermore, regular users typically depend on family members for a daily reminder to use the filter, suggesting that education should foster peer support as well as imparting knowledge.