Health savings accounts held nearly $192 billion across 42.6 million accounts as of June 30, according to the 2026 Midyear HSA Research Report from Devenir Group, an HSA investment solutions firm, but the headline figure understates what actually changed. For the first time in the market’s history, more than half of all HSA dollars were held in investments rather than cash deposits. Investment assets reached $100 billion at midyear, representing 52% of the total and up 37% year-over-year. The account most employers still present as a medical spending tool is increasingly being used as a tax-advantaged savings and investment vehicle.
Accounts holding invested assets carried an average combined balance of $23,837, nearly nine times the average balance of a funded deposit-only account. That divergence reflects account age as much as behavior. Accounts opened in 2004 averaged $36,870, while those opened in 2026 averaged $1,963 at midyear. The direction, however, is consistent. The longer employees hold an HSA, the more likely they are to invest, and the larger the balance grows relative to those who treat the account as a spending vehicle.
Employer-affiliated accounts represent 61% of all HSAs and hold $125 billion, or 65% of total assets, according to the Devenir report. Only 12% of employer-affiliated accounts were unfunded at midyear, compared with 33% of non-employer HSAs. That funding gap is a direct consequence of plan design: employer-sponsored payroll contributions keep accounts active in a way that individually opened accounts often do not sustain. Among funded accounts, non-employer HSAs actually carried a slightly higher average balance at $5,937, compared with $5,496 for employer-affiliated accounts, reflecting the self-directed behavior of individuals who open HSAs independently and contribute more aggressively.
The employer affiliation data sits inside a broader cost-management story. Gallagher’s 2026 Workforce Trends Report: Benefits Benchmarks found that 36 percent of US employers saw health plan premiums rise 10% or more at their last renewal, even after making plan changes, and cost reduction has become the dominant priority reshaping benefits design. High-deductible health plans paired with HSAs remain one of the few plan structures that reduce premium cost for the employer while preserving a tax-efficient savings mechanism for the employee. That dynamic is reflected in the account growth numbers: the HSA market grew by approximately 2.6 million accounts year-over-year to midyear 2026, consistent with continued HDHP adoption across employer groups.
The investment milestone reframes what an HSA program actually is. An account where 52% of assets are invested is no longer primarily a medical spending vehicle. It is a benefits platform that combines near-term healthcare cost coverage with long-term tax-advantaged savings. The investment features of the platform now matter to a meaningful share of enrolled employees: what funds are available, whether a minimum cash threshold must be met before investing is permitted, and whether auto-investment is an option.
In its midyear 2026 report, Devenir projects the market will exceed 49 million accounts and $246 billion in assets by the end of 2028, an updated figure from the firm’s earlier year-end 2025 projection of $234 billion. A portion of that growth will come from the One Big Beautiful Bill Act (OBBB), which as of January 1, reclassified bronze and catastrophic ACA plans as HSA-compatible high-deductible health plans (HDHPs), expanding the pool of eligible account holders. Devenir’s view is that the OBBB’s effect will show up in account growth and contribution activity before it shows up in total assets, an enrollment and education opportunity in the near term rather than an asset story. Employers who already offer an HSA alongside an HDHP may find the eligibility expansion brings in new account holders whose plan designs were previously incompatible, adding both volume and administrative complexity to open enrollment.
High-balance accounts continued their long-term expansion alongside the investment growth. The number of accounts holding at least $10,000 reached 4.4 million at midyear 2026, six times the approximately 707,000 that held that level a decade earlier, according to the Devenir report. Nearly 1.9 million accounts now hold $25,000 or more, roughly fourteen times the 134,000 at midyear 2016. Those accounts are concentrated among longer-tenured holders and are disproportionately invested.
The employer benefits cost pressures pushing more plan sponsors toward HDHPs are, over time, creating a larger cohort of employees with the account tenure and balance size to treat the HSA as a long-term savings vehicle, which in turn raises the bar on what a well-designed HSA program needs to offer.
