What’s Driving Medical Stop-Loss Costs for Self-Funded Employers?

Why historical claims data provides an incomplete picture

For many years, insurers could look at past claims experience and make reasonably accurate projections about future performance. Costs increased in ways that were familiar and easier to predict. Today, healthcare is changing much faster.

New treatments are reaching the market more quickly. Care is becoming more specialized. Some conditions that once required years of treatment can now be addressed through therapies that cost millions of dollars upfront.

As a result, historical claims data is no longer enough. If your organization sponsors a self-funded health plan, understanding today's emerging therapies and cost trends is just as important as understanding last year's claims experience.

What is driving higher medical stop-loss claims costs?

Historically, catastrophic claims were often tied to major accidents, organ transplants, premature births, or lengthy hospital stays. Those claims haven't disappeared, but specialty pharmaceuticals and advanced therapies play a much larger role in driving costs.

Gene therapies, CAR-T treatments, and other breakthrough medications deliver life-changing outcomes for patients with serious and rare conditions. Some therapies cost more than $2 million per patient, while others cost $4 million or more. In fact, several newly approved gene therapies now exceed $3 million per treatment, underscoring how dramatically claim severity has shifted in recent years.

For self-funded employers, a single high-cost claimant can create a level of financial exposure that would have been uncommon just a few years ago. Claim frequency still matters, but claim severity is becoming increasingly important when evaluating healthcare risk.

Healthcare inflation adds to claims costs

Healthcare inflation also plays a role. As the cost of delivering care continues to rise, those expenses eventually make their way into claims costs and stop-loss pricing.

How GLP-1 utilization affects health plan cost planning

GLP-1 medications are one example of how healthcare cost drivers have changed over the past decade. While they don't typically generate the multimillion-dollar claims associated with gene therapies, their rapid adoption prompts many self-funded employers to take a closer look at long-term healthcare costs. Utilization continues to grow, but the industry is still assessing how widespread use may affect future healthcare spending, claims activity, and overall plan costs.

The same is true for many emerging therapies. Understanding how these treatments could affect future healthcare costs is becoming increasingly important for self-funded employers. As utilization grows, new therapies may affect stop-loss costs and long-term benefits planning.

That's why organizations with self-funded health plans are paying close attention to where the next high-cost claim could come from and how quickly medical innovation may change the healthcare landscape.

How insurance carriers assess emerging stop-loss risks

The insurance industry has always relied on data. The difference today is the pace of change.

A treatment that was rarely discussed a few years ago can now meaningfully influence claims activity. New medical technologies can reshape healthcare costs and treatment decisions faster than traditional forecasting models can adapt.

Analytics support claims and pharmacy risk assessment

Many insurance carriers use machine learning to help identify trends and emerging risks earlier. However, data alone doesn't tell the full story.

These tools influence how carriers assess your organization's risk, which can ultimately affect stop-loss pricing and renewal discussions. As healthcare costs become less predictable, carriers are taking a closer look at factors such as claims experience, pharmacy utilization, and the potential impact of emerging therapies.

Advanced analytics are increasingly being used to identify potential catastrophic claims, analyze pharmacy utilization patterns, support clinical risk stratification, and improve overall underwriting decision-making.

Why underwriting judgment remains important

Technology can help identify patterns, but understanding what those patterns mean still requires experience and context. As a result, expect underwriting reviews to become more detailed and more individualized than they were in the past.

What changing underwriting means for stop-loss renewals

Faced with larger claims and greater uncertainty, carriers are evaluating the risks they assume more closely. For organizations sponsoring self-funded health plans, these pressures can affect renewal pricing, coverage terms and underwriting requirements.

Potential changes in pricing, deductibles and underwriting reviews

At renewal, your organization may encounter:

• Higher stop-loss premiums.
• Higher deductibles before stop-loss coverage applies.
• More detailed underwriting reviews.
• Closer examination of pharmacy utilization.
• More individualized assessments of higher-risk groups.

How reinsurance conditions can affect carriers

Early 2026 brought another reminder of these pressures when several reinsurers exited the U.S. medical stop-loss market. While capacity remains available, rising claim costs influence underwriting and pricing decisions throughout the market. Many reinsurers are also placing greater emphasis on underwriting profitability and encouraging carriers to retain more risk, reinforcing discipline across the market.

Industry observers expect the current hardening market environment to persist for the near future as carriers and reinsurers continue adjusting to rising catastrophic claim costs and evolving healthcare risks.

Stop-loss coverage remains an important safeguard against catastrophic claims, but managing that risk is becoming more complex.

How self-funded employers can prepare for renewal

As new therapies enter the market and healthcare costs rise, self-funded health plans may face greater volatility in claims costs and stop-loss pricing. These treatments create new possibilities for patients while changing the financial risks associated with employer-sponsored healthcare coverage.

Although employers cannot control medical inflation or the pace of pharmaceutical innovation, they can prepare for the potential impact. Reviewing claims experience and pharmacy utilization, assessing cost containment and clinical risk management practices, and identifying potential high-cost exposures can support more informed renewal decisions.

Connect with a Brown & Brown medical stop-loss reinsurance specialist

Understanding what these trends mean for your plan can be challenging, particularly when evaluating higher renewal costs, deductible changes and more detailed underwriting requirements.

Brown & Brown’s medical stop-loss reinsurance specialists bring experience in program design and placement to help you assess these considerations.

Connect with our team to discuss your organization’s cost concerns, renewal challenges and options for managing high-cost claims exposure.