The Centers for Medicare & Medicaid Services canceled about 315,000 Affordable Care Act health plans covering approximately 760,000 people last month after identifying unverified citizenship or immigration documentation and other suspected enrollment problems, according to documents published in the Federal Register.

CMS also announced plans to bar 569 insurance brokers and agents after identifying what the agency described as “statistically implausible” rates of 2026 plan applications that lacked basic applicant information, including Social Security numbers.

The agency said some brokers and agents allegedly enrolled consumers without their consent, changed existing plans without authorization, submitted inaccurate information or created questionable applications to collect commissions. CMS said those practices can result in improper federal premium-tax-credit payments while leaving consumers with unexpected coverage changes, medical bills and potential tax problems.

The crackdown is also imposing an immediate industry-wide freeze on new Obamacare broker registrations through an emergency-style rulemaking process. Brokers who do not have a 2026 registration will remain subject to the freeze until Feb. 1, 2027.

CMS estimates that unauthorized enrollments could result in as much as $6.6 billion in improper federal spending during the 2026 plan year. The agency has previously adopted measures aimed at strengthening oversight of agents and brokers, including requirements designed to document consumer consent and confirm the accuracy of Marketplace applications.

The Affordable Care Act, signed into law by then-President Barack Obama in 2010, created the health insurance Marketplace and provides subsidies based on household income. The Trump administration has pursued changes to the program while increasing scrutiny of eligibility and enrollment practices.