We study the effect of the US Affordable Care Act (ACA) on healthcare borrowing costs. The ACA provides insurance subsidies to low-income enrollees. States could accept funding to expand Medicaid, although many declined, citing the cost burden. The ACA significantly reduced healthcare yields after a favorable 2012 Supreme Court ruling. Furthermore, hospital investment spending increased, and investment-cash flow sensitivities decreased. The yield effect was double in Medicaid expansion states, and insignificant in rural areas of non-expansion states. Our results highlight how the municipal market can be used to evaluate the heterogeneous effects of public policy and guide a targeted policy approach. (C) 2021 Elsevier B.V. All rights reserved.