In 2014, qualified health plans sold in the Affordable Care Act (ACA) marketplaces were accused of providing drug coverage that was too restrictive and costly. After the change in administration in 2016, efforts to repeal portions of the ACA led to increases in premiums, decreases in enrollment, and overall uncertainty. To examine how the number of formulary tiers and medication cost sharing, as well as transparency around these aspects, in qualified bronze and silver health plans in California, Florida, and Illinois changed from 2014 to 2018. A search of all bronze and silver qualified health plans in California, Florida, and Illinois was performed in 2014 and in 2018 through the marketplace and issuer websites. From 2014 to 2018, the total number of bronze and silver qualified health plans offered in California, Florida, and Illinois remained relatively stable (36 to 35, 123 to 122, and 60 to 74, respectively). Over the same time period, the median number of formulary tiers remained constant for California and Florida (four and five) and increased from five to seven for Illinois. Of note, most Illinois plans shifted from a formulary with five or fewer tiers (92% of plans) to seven tiers (73% of plans) between 2014 and 2018. There was also an increase in the use of coinsurance instead of copay for each of the four following formulary tiers: generic (19% to 27% of plans), preferred brand (21% to 38%), nonpreferred brand (33% to 52%), and specialty (76% to 91%). Additionally, there was an increase in the median coinsurance rates for each of the aforementioned tiers: 0% to 25%, 0% to 35%, 30% to 40%, and 30% to 40%, respectively. The proportion of plans that provided their formularies on the marketplace website increased from 82% to 97% from 2014 to 2018, with the increase mostly driven by California plans (0% to 80%). There was a small increase in the proportion of plans that reported medication cost sharing through the medical benefit from 2014 (19%) to 2018 (25%). Between 2014 and 2018, qualified health plans increased their use of formularies with greater numbers of tiers, the use of coinsurance for each tier, and higher coinsurance rates. Availability of formularies on marketplace websites increased, but cost sharing transparency for medications covered by the medical benefit could greatly improve. No funding supported this study. Hung reports past employment by Blue Cross Blue Shield Association, CVS Health, and a grant from PhRMA outside of the submitted work. She was an intern at the Biotechnology Industry Organization when this work began. Sauvageau has no disclosures. This work was presented as a poster at the AMCP 2018 Managed Care & Specialty Pharmacy Annual Meeting; April 23-26, 2018; Boston, MA.