Medicaid spent $1,835.34 per enrollee on emergency department visits in Connecticut between 2018 and 2024. In California, that number was $310.69. Both states run large, mature Medicaid programs. The nearly 6-fold gap between them isn't a rounding error — it's a window into how differently states structure, price, and use emergency care under the same federal program.

A $1,500 Gap That Runs Coast to Coast

The state-level variation in Medicaid ED spending is wide enough to suggest these are effectively different programs operating under the same name.

Connecticut's $1,835.34 per-enrollee figure stands out even against other high-spending states. New Jersey, with more than twice as many enrollees, still reached $1,520.98 per enrollee. California, the largest Medicaid program in the country at nearly 14.7 million enrollees and $4.6 billion in total ED spending, lands at $310.69. Total volume doesn't explain the gap. Rate structures, utilization patterns, and what states choose to reimburse do.

For taxpayers and program administrators, the practical consequence is stark: two states with similar demographic profiles can face ED cost burdens that differ by a factor of five or six, with no automatic mechanism to explain or correct that divergence.

Reimbursement Rates Are Rising Everywhere, Regardless of Volume

Whatever is driving state-level variation, one trend cuts across all of them. The average paid per ED claim rose from $94.87 in 2018 to $142.06 in 2024, a 50% increase over six years with no single year showing a decline.

COVID produced a sharp drop in claim volume — national ED claims fell from 67,678,518 in 2019 to 52,916,098 in 2020, a loss of roughly 14.7 million claims in a single year. But average reimbursement per claim actually rose during that period, from $97.95 to $109.54. Volume recovered quickly: by 2023, total ED claims reached 79,623,706, and unique Medicaid beneficiaries receiving ED care peaked at 71,969,330, up from 56,733,972 in 2018.

The combination of rising per-claim reimbursement and recovering volume means total program costs have grown substantially even as the per-claim rate increase looks modest in isolation. If the per-claim average continues rising at its recent pace, the cost implications compound fast across a program that now serves tens of millions of ED visits annually.

High-Acuity Billing Doesn't Follow Primary Care Access

The acuity data adds another layer to the state variation story, and it complicates a common assumption about how primary care access affects ED use.

Illinois billed 2,867,115 high-acuity (99285) ED claims against only 267,371 low-acuity claims, producing a high-to-low acuity ratio of 10.72 — the highest in the dataset, and nearly three times Maryland's ratio of 3.79. High acuity billing at that scale has direct cost consequences, since 99285 carries the highest reimbursement of any ED visit code.

Kentucky presents the most striking case. It recorded 2,707.8 high-acuity ED visits per 1,000 enrollees, the highest rate in the acuity analysis. At the same time, it logged 33,043.4 primary care E/M claims per 1,000 enrollees, also among the highest in the dataset. Maryland, by contrast, had 725.5 high-acuity ED visits per 1,000 enrollees alongside 17,571.7 primary care E/M claims per 1,000 enrollees. Kentucky's primary care volume is nearly double Maryland's, yet its high-acuity ED utilization rate is more than three times higher.

That pairing — high primary care volume and high high-acuity ED use coexisting in the same state — raises a question the spending data alone can't settle: whether Kentucky's ED acuity figures reflect genuine clinical severity, coding practices, or some combination of both. The answer matters enormously, because the entire logic of investing in primary care access as an ED cost-reduction strategy rests on the assumption that the two move in opposite directions.