Delays in seeking medical attention for patients with acute coronary syndromes (ACS) preclude early application of life-saving treatment and diminish efficacy. Previous studies suggest 3-hour delays between onset of symptoms and ED arrival in patients with typical presentations of acute myocardial infarction (AMI). A prospective observational study was conducted in an urban ED measuring lag time (LT) among adults presenting within 48 hours of onset of symptoms suggestive of ACS. Univariate and multiple regression analyses were performed on 5 predictors: age, sex, symptoms at presentation, and 2 different outcomes (AMI and ACS). Three hundred seventy-four patients were enrolled. Mean age was 63 years with 38% 70 years or older. Seventy-three percent of all patients with suspected ACS presented with chest pain, 27% with atypical symptoms. Overall mean LT was 8.7 hours (standard deviation 11). In subgroup analysis, patients aged >/=70 years were more likely to have LTs >12 hours (29% vs. 19% P =.043) and patients without chest pain had longer mean LTs (11.6 vs. 7.6 hours, P =.01). Delay in ED presentation is group specific. Advanced age and patients with atypical symptoms are predictive of longer LTs. Contrary to previously published data, patients with symptoms suspicious for ACS can delay an average of 9 hours, which might alter current thinking in the prevention and care of these patients.