Top 20 HSA Market Concentration – 2025 Midyear Update

Using data from our 2025 Midyear HSA Research Report, we measured HSA market concentration using the Herfindahl-Hirschman Index (HHI) and found it increased 8% to 1,409 from 1,302 a year ago. This growth was driven primarily by strong equity market performance, which boosted investment asset values, along with continued organic account growth among the largest HSA providers. Despite this increase, concentration within the HSA market currently remains minor according to the index. Market share, as measured by total assets, is now 75% among the top 5 providers, up from 73% at the 2024 midyear point.

This continues a multi-year trend of gradual concentration. In our 2024 midyear update, we found the HHI had increased 10% from the previous year to 1,302, driven by sustained market share growth among the largest HSA providers through a combination of organic growth and M&A activity.

As the HSA market continues to mature, we anticipate concentration trends primarily will be influenced by equity market performance (which disproportionately grows investment assets held by larger providers) and the competitive advantages that scale provides to leading HSA providers, including technology investments, brand recognition, and the ability to serve large employer groups. Devenir will continue monitoring these dynamics and provide updates as the market evolves. If you have any comments or questions, feel free to contact our research team at [email protected].

HHI Index (Max 10,000)

Methodology: Market concentration is measured using the Herfindahl-Hirschman Index (HHI) and the market shares (as measured by total assets) of the top 20 largest HSA providers. The HHI is calculated by squaring the market share of each firm competing in the market and then summing the results. For example, for a market consisting of four firms with shares of 30, 30, 20, and 20 percent, the HHI is 2,600 (30² + 30² + 20² + 20² = 2,600). A higher HHI generally indicates a higher level of concentration and a less competitive market.