Medicare Advantage and Part D insurers began issuing 2027 Annual Notice of Change letters this week ahead of a September 30 federal deadline. The mailings warn millions of enrollees of higher premiums and altered benefits as the Centers for Medicare & Medicaid Services requires the notices before open enrollment opens October 15.

The enhanced premium subsidy that cushioned drug plan costs is set to end, raising financial stakes for beneficiaries. Analysts at KFF have documented rising base premiums and plan exits in several markets, leaving some enrollees to choose new coverage.

Each notice details changes to premiums, deductibles, drug formularies and provider networks for the coming year. The Medicare Rights Center and other consumer advocates urged recipients not to discard the letters and to compare options during the open enrollment window closing December 7.

The subsidy expiry compounds pressure on a program already reshaped by the $2,000 annual out-of-pocket cap on Part D drug spending under the Inflation Reduction Act. Major insurers including UnitedHealthcare, Humana and CVS Health's Aetna have signaled premium and plan design adjustments in response.

A Medicare Rights Center spokesperson said: "Every beneficiary should read their notice carefully and shop their plan this year," warning that automatic renewal could leave seniors in costlier coverage.