The United States spends substantially more per capita for healthcare than any other nation. Defensive medicine is 1 source of such spending, but its extent is unclear. Using a national survey of approximately 1500 US hospitalists, we report the estimates the US hospitalists provided of the percent of resources spent on defensive medicine and correlates of their estimates. We also ascertained how many reported being sued. Sixty-eight percent of eligible recipients responded. Overall, respondents estimated that 37.5% of healthcare costs are due to defensive medicine. Just over 25% of our respondents, including 55% of those in practice for 20 years or more, reported being sued for medical malpractice. Veterans Affairs (VA) hospital affiliation, more years practicing as a physician, being male, and being a non-Hispanic white individual were all independently associated with decreased estimates of resources spent for defensive medicine. Journal of Hospital Medicine 2018;13:26-29. Published online first August 23, 2017.