Objectives: I examined how labor market and health insurance outcomes were affected by the loss of dependent coverage eligibility under the Patient Protection and Affordable Care Act (ACA). Methods: I used National Health Interview Survey (NHIS) data and regression discontinuity models to measure the percentage-point change in labor market and health insurance outcomes at age 26 years. My sample was restricted to unmarried individuals aged 24 to 28 years and to a period of time before the ACA's individual mandate (2011-2013). I ran models separately for men and women to determine if there were differences based on gender. Results: Aging out of this provision increased employment among men, employersponsored health insurance offers for women, and reports that health insurance coverage was worse than it was 1 year previously (overall and for young women). Uninsured rates did not increase at age 26 years, but there was an increase in the purchase of non-group health coverage, indicating interest in remaining insured after age 26 years. Conclusions: Many young adults will turn to state and federal health insurance marketplaces for information about health coverage. Because young adults (aged 18-29 years) regularly use social media sites, these sites could be used to advertise insurance to individuals reaching their 26th birthdays.