BackgroundCardiac implantable electric devices are commonly used to treat heart failure. Little is known about temporal and geographic variation in use of cardiac resynchronization therapy (CRT) devices in usual care settings.Methods and ResultsWe identified new CRT with pacemaker (CRT‐P) or defibrillator generators (CRT‐D) implanted between 2008 and 2013 in the United States from a commercial claims database. For each implant, we characterized prior medication use, comorbidities, and geography. Among 17 780 patients with CRT devices (median age 69, 31% women), CRT‐Ps were a small and increasing share of CRT devices, growing from 12% to 20% in this study period. Compared to CRT‐D recipients, CRT‐P recipients were older (median age 76 versus 67), and more likely to be female (40% versus 30%). Pre‐implant use of β‐blockers and angiotensin‐converting enzyme inhibitors or angiotensin II receptor blockers was low in both CRT‐D (46%) and CRT‐P (31%) patients. The fraction of CRT‐P devices among all new implants varied widely across states. Compared to the increasing national trend, the share of CRT‐P implants was relatively increasing in Kansas and relatively decreasing in Minnesota and Oregon.ConclusionsIn this large, contemporary heart failure population, CRT‐D use dwarfed CRT‐P, though the latter nearly doubled over 6 years. Practice patterns vary substantially across states and over time. Medical therapy appears suboptimal in real‐world practice.