The Effect of State Copay Accumulator Bans on Premiums in Commercial Health Insurance Markets

Abstract Background Copay cards are used by pharmaceutical manufacturers to lower patient out-of-pocket (OOP) costs and increase patient adherence. Pharmacy benefit managers (PBMs) assert these programs increase premiums. PBMs use accumulators to prevent these funds from counting toward patient deductibles or OOP maximums. Federal regulations prohibit accumulators in certain situations but are generally not enforced due to concerns that premiums will rise. Accumulators are banned in 27 states and the District of Columbia. This paper leverages state-level data to explore whether there is a relationship between state accumulator bans and premiums. Methods Using 2014-2024 Medical Loss Ratio (MLR) filing data for small and large group issuers and information on state policies, we used staggered difference-in-differences methods to estimate the effect of state bans on premiums. Results From 2020-2024, average premiums in states that enacted bans grew slower (20.8%) than in states that did not (24.2%). There was no statistically significant difference in average annual premiums in states with bans had bans not been implemented ($41.08 [95% CI: -$151.28 to $233.43]). This was consistent across specifications. Conclusion The evidence does not support concerns that copay accumulator bans increase premiums.