State Insulin Caps Left Most Insured Adults Uncovered

Key Takeaways

• Among commercially insured United States adults aged 18 to 64 years with insulin-treated diabetes, Wang and colleagues reported that some form of state insulin cap was in place in 29 states and Washington, D.C., by 2026.
• The analysis estimated that approximately 0.99 million adults with insulin-treated diabetes were covered by an applicable state-regulated plan in 2026.
• Approximately 2.9 million commercially insured adults with insulin-treated diabetes remained outside state insulin-cap protections, including about 2.2 million enrolled in federally regulated commercial plans outside state jurisdiction.
• An additional 0.67 million adults with insulin-treated diabetes were enrolled in state-regulated plans but lived in states without an insulin out-of-pocket cap.

Insulin affordability remains a practical problem for commercially insured adults who use insulin, and the presence of a state out-of-pocket cap does not mean every commercially insured resident is eligible for its protections. For working-age adults, eligibility depends in part on where they live and whether their commercial coverage is regulated by the state or at the federal level. Investigators therefore estimated how much of this population was eligible for state insulin-cap protections.

In an analysis of state insulin cap eligibility, Wang and colleagues identified insulin out-of-pocket cap legislation enacted through 2026 across the states and Washington, D.C. The analysis focused on adults aged 18 to 64 years with diabetes who used insulin and had commercial insurance. Using public data on diabetes prevalence and health insurance coverage, investigators estimated the population eligible and exposed to state out-of-pocket cap legislation: adults using insulin who were enrolled in state-regulated commercial plans and lived in states that had enacted insulin caps.

By 2026, 29 states and Washington, D.C., had enacted insulin out-of-pocket caps. Investigators estimated that approximately 0.99 million adults with diabetes who used insulin were enrolled in state-regulated commercial plans and lived in jurisdictions with these protections.

Despite the spread of state caps, substantially more commercially insured adults with insulin-treated diabetes remained outside their reach. Approximately 0.67 million adults using insulin were enrolled in state-regulated commercial plans but lived in states without an insulin out-of-pocket cap. Another 2.2 million were enrolled in federally regulated commercial plans, which fall outside state jurisdiction. The findings demonstrate that insurance jurisdiction limits the reach of state insulin-cap legislation. Even in states that have enacted caps, federally regulated commercial plans are outside the scope of state insurance regulation. Conversely, adults with state-regulated commercial coverage may remain unprotected if they live in a state without an insulin cap.

The analysis evaluated the estimated reach of insulin-cap policies rather than their effects on actual out-of-pocket spending, insulin utilization, or clinical outcomes. The findings therefore describe how many commercially insured adults with insulin-treated diabetes may fall within or outside state-level protections, rather than demonstrating whether the laws reduced individual patients' insulin costs or improved diabetes outcomes.

By 2026, state insulin caps had extended potential financial protections to approximately 0.99 million commercially insured adults with insulin-treated diabetes, but their overall reach remained limited. Approximately 2.9 million adults remained outside state cap protections, largely because they were enrolled in federally regulated commercial plans or lived in states without applicable legislation. The investigators concluded that federal legislative efforts are needed to further reduce the financial burden of insulin therapy.

Clinician Questions

Who is left out of state insulin cap laws among commercially insured adults using insulin? The population outside state insulin-cap protections included adults with insulin-treated diabetes enrolled in federally regulated commercial plans outside state jurisdiction, as well as adults with state-regulated commercial coverage who lived in states without an insulin out-of-pocket cap.

What did the 2026 state insulin cap analysis measure, and what did it not measure? Wang and colleagues estimated eligibility for state insulin-cap protections among U.S. adults aged 18 to 64 years with diabetes who used insulin and had commercial insurance. The analysis combined information on state insulin-cap legislation with public data on diabetes prevalence and health insurance coverage. It estimated policy reach rather than actual out-of-pocket insulin spending, insulin utilization, or clinical outcomes.

What do the findings suggest about the limitations of state insulin caps? State legislation can apply to state-regulated commercial insurance but cannot regulate federally regulated commercial plans. As a result, state caps can reduce potential insulin cost exposure for eligible enrollees while leaving a substantial proportion of commercially insured adults with insulin-treated diabetes outside their reach. The investigators concluded that federal legislative efforts are needed to further reduce the financial burden associated with insulin therapy.