The extent to which recent large increases in hospitals’ adoption of electronic health record (EHR) systems can be attributed to the Health Information Technology for Economic and Clinical Health (HITECH) Act of 2009 is uncertain and debated. Because only short-term acute care hospitals were eligible for the act’s meaningful-use incentive program, we used national hospital data to examine the differential effect of HITECH on EHR adoption among eligible and ineligible hospitals in the periods before (2008–10) and after (2011–15) implementation of the program. We found that annual increases in EHR adoption rates among eligible hospitals went from 3.2 percent in the pre period to 14.2 percent in the post period. Ineligible hospitals experienced much smaller annual increases of 0.1 percent in the pre period and 3.3 percent in the post period, a significant difference-in-differences of 7.9 percentage points. Our results support the argument that recent gains in EHR adoption can be attributed specifically to HITECH, which suggests that the act could serve as a model for ways to drive the adoption of other valuable technologies.