Medical Loss Ratio — UNH Margin Signal

The Medical Loss Ratio (MLR = medical costs paid / premiums earned) is the single most watched metric for managed care companies.

UnitedHealth (UNH), as the largest US health insurer (~$370B revenue), sets the tone for the entire managed care sector.

MLR above guidance is a direct earnings risk signal — the company must pay out more in claims than budgeted.

UnitedHealth's Optum health services segment (pharmacy benefits, physician groups, analytics) provides partial offset to MLR volatility — when MLR spikes, Optum margins provide a cushion.

But the MLR surprise's magnitude determines whether the Optum buffer is sufficient. 2024 saw MLR surge to 85.7% (vs guidance of 84.6%) due to Medicare Advantage utilization normalization post-COVID — UNH declined 20%+ in a single session.