Email Nudges Increased Eligibility Verification And Subsidy Receipt In California's ACA Marketplace.

In the Affordable Care Act (ACA) Marketplaces, enrollees must periodically demonstrate their eligibility to receive income-linked health insurance premium subsidies. Marketplaces can verify eligibility using existing records, but only with consumers' consent, which must be renewed at specified times. In a randomized experiment in September 2020, we tested the effect of email nudges reminding consumers to provide consent for verification of their continued eligibility for premium subsidies in California's ACA Marketplace. More than 20,000 households that had applied for subsidies but whose consent for eligibility verification would soon expire were sent one, two, or three emails reminding them to renew consent. Sending three emails increased consent updates by 1.9 percentage points (3.2 percent) and increased receipt of subsidies by 2.0 percentage points (4.0 percent). However, nearly 40 percent of households receiving three emails did not update their consent by the end of the open enrollment period, thus preventing their continued receipt of subsidies. To improve the affordability of Marketplace coverage, new policies and structural changes may be needed to reduce administrative barriers that can inhibit access to subsidies.