ABSTRACTAntimicrobial resistance inEnterobacteriaceae, including resistance to carbapenems, is increasing worldwide. However, using U.S. Study for Monitoring Antimicrobial Resistance Trends (SMART) data for 2009 to 2013, no statistically significant decreasing susceptibility trends were found overall forEscherichia coliisolates from patients with intra-abdominal infections. In the subset of isolates from community-associated infections, susceptibility to levofloxacin decreased significantly and the increasing rate of multidrug-resistantE. coliapproached statistical significance. In 2013, ertapenem, imipenem, and amikacin showed the highest susceptibility rates (≥99%) and fluoroquinolones the lowest (<70%). The 10 non-ertapenem-susceptible isolates (0.3% of allE. coliisolates) encoded one or more carbapenemases, extended-spectrum β-lactamases (ESBLs), AmpC β-lactamases, or non-ESBL β-lactamases.