Objective: To test the hypothesis that frequency of attendance at religious services is inversely related to prevalence of hypertension and blood pressure level.Methods: In the Third National Health and Nutrition Examination Survey (NHANES III), 14,475 American women and men aged 20 years and over reported frequency of attendance at religious services, history of hypertension treatment, and had blood pressure (BP) measured.Results: The percentage reporting attending religious services weekly (52 times/yr) was 29 and more than weekly (>52 times/yr) was 10. Prevalence of hypertension (systolic BP > or = 140 or diastolic BP > or = 90 mm Hg or current use of blood pressure medication) was 21% in never at attenders, 19% in those attending less than weekly (1-51 times/yr), 26% in those attending weekly, and 26% in those attending more than weekly (p < .01). After controlling for sociodemographic and health variables, religious attendance was associated with reduced prevalence compared with nonattendance, significantly so for weekly (beta = -0.24; 95% confidence interval [CL], -0.37 to -0.11; p < .01) and more than weekly (beta = -0.33; 95% CL, -0.60 to -0.07; p < .05). No significant effect modification by gender or age was observed. Compared with never attenders, persons attending weekly had a systolic BP 1.46 mm Hg (95% CL 2.33, 0.58 mm Hg, p < .01) lower and persons attending >52 times/yr had systolic BP 3.03 mm Hg (95% CL 4.34, 1.72 mm Hg, p < .01) lower. No significant effect modification by gender was observed; these estimates are adjusted for a significant interaction between age and less than weekly attendance (1-51 times) (p < .05).Conclusions: Compared with never attending, attendance at religious services weekly or more than weekly was associated with somewhat lower adjusted hypertension prevalence and blood pressure in a large national survey.