To (1) assess whether hospitals in states requiring explicit patient consent ("opt-in") for health information exchange (HIE) are more likely to report regulatory barriers to HIE and (2) analyze whether these policies correlate with hospital volume of HIE.Cross-sectional analysis of US nonfederal acute care hospitals in 2016.We combined legal scholarship surveying HIE-relevant state laws with the American Hospital Association Annual Information Technology Supplement for regulatory barriers and hospital characteristics. Data from CMS reports for hospitals attesting to Meaningful Use stage 2 (MU2; renamed "Promoting Interoperability" in 2018) in 2016 captured hospital HIE volume. We used multivariate logistic regression and linear regression to estimate the association of opt-in state consent policies with reported regulatory barriers and HIE volume, respectively.Hospitals in states with opt-in consent policies were 7.8 percentage points more likely than hospitals in opt-out states to report regulatory barriers to HIE (P = .03). In subgroup analyses, this finding held among hospitals that did not attest to MU2 (7.7 percentage points; P = .02). Among hospitals attesting, we did not find a relationship between opt-in policies and regulatory barriers (8.0 percentage points; P = .13) or evidence of a relationship between opt-in policies and HIE volume (β = 0.56; P = .76).Our findings suggest that opt-in consent laws may carry greater administrative burdens compared with opt-out policies. However, less technologically advanced hospitals may bear more of this burden. Furthermore, opt-in policies may not affect HIE volume for hospitals that have already achieved a degree of technological sophistication. Policy makers should carefully consider the incidence of administrative burdens when crafting laws pertaining to HIE.