How ACA changes are set to reshape the health insurance landscape

The health insurance landscape in the United States is undergoing a period of change, putting the future of the Affordable Care Act (ACA) exchanges at a crossroads. While the ACA exchanges have seen record enrollments fueled by enhanced premium subsidies and simplified enrollment procedures, a wave of funding cuts and policy shifts could impact these gains, potentially reshaping coverage options for millions of Americans and influencing access and affordability in the insurance market.

As premium subsidies face expiration and federal support for enrollment assistance diminishes, insurers are recalibrating their participation strategies. Some have seized expansion opportunities, while others have signaled their exit from the marketplace. These moves underscore the financial and operational pressures within the exchange market, driven by evolving regulations and shifting utilization patterns.

Here are the most impactful changes on the horizon.

Expiration of enhanced subsidies and funding cuts

At the federal level, several key changes are expected to impact how consumers access and retain coverage. Without Congressional intervention, enhanced subsidies will sunset at the end of 2025, triggering an average 75% premium increase for subsidized enrollees in 2026. Industry analysts expect this to push millions out of the marketplace, leaving a smaller, higher-risk pool. At the same time, funding cuts to navigator programs that support in-person enrollment are expected to reduce assistance for vulnerable populations that rely on help navigating the enrollment process.

Changes to enrollment periods and procedures

The federal government is also tightening enrollment procedures. The open enrollment period has been shortened by one month and now ends on December 15. During the most recent enrollment cycle, roughly 40% of consumers enrolled after December 15, indicating that the shorter enrollment window could lead to lower overall enrollment.

Alongside this, new enrollment rules are being put into place to tighten verification requirements. Starting August 1, marketplaces will require all applicants to submit documentation to verify income, immigration status, family size, and insurance coverage, replacing automated database checks. This change adds new hurdles, particularly for low-income enrollees.

The end of automatic re-enrollment means consumers must actively reapply each year, while restrictions on special enrollment periods (SEPs) will end year-round enrollment opportunities for low-income individuals and block states from offering such options.

Insurers will also be allowed to deny coverage to applicants with any outstanding premium debt. Additionally, subsidies will no longer be granted during the application review period, requiring eligibility confirmation upfront; this includes cases involving major life events.

Eligibility rollbacks for specific populations

Eligibility criteria are narrowing for specific groups. Marketplace subsidies will no longer be available to many lawfully present immigrants, particularly those subject to the five-year Medicaid waiting period who earn below 100% of the federal poverty level. Deferred Action for Childhood Arrivals (DACA) recipients (often referred to as Dreamers) will lose eligibility to enroll in or purchase plans through the ACA marketplace.

What this means for the business of healthcare

For payors, rising churn and uncertain subsidy levels may affect risk pools, claims forecasting, and benefit design. If coverage lapses become more prevalent, providers and health systems could face increased uncompensated care and patient acuity challenges.

The ripple effects could extend further. For life sciences and digital health companies, the potential for reduced coverage and more fragmented enrollment could shrink addressable markets and complicate patient access and adherence, particularly among low-income and medically complex populations.

Health equity could also take a hit. Populations that have benefited most from the ACA's expanded subsidies—communities of color, rural residents, and those with limited English proficiency—are the ones most likely to be affected by stricter enrollment and eligibility rules.

Insurer strategies are shifting

With premium subsidies set to expire and federal support for enrollment assistance lessening, insurers are already recalibrating their marketplace strategies. Some, like Centene and UnitedHealthcare, are expanding their presence ahead of these changes. In 2025, Centene, the largest marketplace insurer, expanded into Iowa, while UnitedHealthcare entered four new states: Indiana, Iowa, Nebraska, and Wyoming.

At the same time, other insurers are contracting. CVS/Aetna has announced plans to exit the marketplace entirely in 2026, citing persistent financial losses. Cigna is also scaling back, withdrawing from select counties and three states while maintaining a presence in several core markets.

These diverging strategies reflect the varied responses to shifting policy dynamics, enrollment trends, and mounting financial pressures across the ACA landscape. Smaller and mid-sized carriers may face the greatest challenges, potentially triggering further consolidation in the marketplace.

At the same time, the exchanges operate within a broader insurance ecosystem. Commercial enrollment trends remain unsettled, and growth in Medicare continues to shift payor priorities and resource allocation. For multi-line carriers balancing risks across markets, these factors add layers of complexity to strategic planning.

Preparing for insurance market disruption

The ACA marketplace is entering a period of disruption; one that will reshape how coverage is accessed, how care is reimbursed, and how financial risk is distributed across the healthcare system. Without decisive legislative or administrative action, many Americans could find it harder and more expensive to get and stay covered.

For healthcare organizations, the challenge is not only to keep pace with shifting policy but to anticipate its broader impacts: Where insurers are expanding or retreating, which populations are most at risk, and how regional markets are evolving.

Definitive Healthcare helps healthcare organizations navigate this complexity with real-time intelligence on providers, population trends, and market dynamics—as well as access to medical and prescription claims—empowering your teams to plan proactively and respond with confidence. Get a demo today.