OBJECTIVE The objective was to estimate emergency department (ED) visits for Clostridium difficile infection in the United States for the years 2006 through 2010. METHODS Estimates of ED visits for C. difficile infection were calculated in patients 18 years and older using the Nationwide Emergency Department Sample. RESULTS During the calendar years 2006 through 2010, there were an estimated total of 491,406,018 ED visits. Of these, 462,160 ED visits were associated with a primary International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis of C. difficile. The C. difficile infection ED visit rate (visits/100,000 census population) increased from 34.1 in 2006 to 42.3 in 2010, an increase of 24% (p < 0.01). There was also a significant overall increased trend in the number of ED visits for C. difficile from 2006 through 2010 (p < 0.01). The highest ED visit rate for C. difficile was observed for patients 65 years and older (163.18 per 100,000), while the lowest visit rate was for patients aged 18 to 24 years (5.10 per 100,000). The greatest increase in C. difficile infection visits occurred in the age group 18 to 24 years. CONCLUSIONS These results indicate an increased trend of ED visits for C. difficile in the period 2006 through 2010 with an overall population-adjusted increase of 24%. This represents important complementary data to previous studies reporting an increase in the rate of C. difficile infections in the U.S. hospitalized population.