ANOC vs EOC: the two Medicare letters a parent gets each fall

Last reviewed August 2026

The Annual Notice of Change is the plan’s focused summary of what will change on January 1, while the Evidence of Coverage is the complete reference for the plan’s coverage, costs, and rules. The ANOC must reach current enrollees first, by September 30, and the EOC must arrive by October 15.

What is the ANOC?

The Annual Notice of Change is a plan’s short annual summary of the coverage, cost, and benefit changes that take effect January 1 of the coming year.

The plan sends it as a stand-alone document so an enrollee can focus on what is changing rather than search the full plan handbook for each update.

What is the EOC?

The Evidence of Coverage, sometimes called the member handbook, is the plan’s detailed record of what it covers, what the member pays, and the rules for using the plan.

It is the complete reference for the coverage year, not a summary limited to changes from the previous year.

How are the ANOC and EOC different?

The ANOC answers what changed for the coming year, while the EOC provides the full rule or cost behind a specific part of the plan.

Which one should a family read first?

The ANOC comes first and is the focused document for seeing what changed, while the EOC is the reference for checking the exact rule or cost behind a listed change.

Reading them in that order follows the way CMS separates the mailings: the stand-alone change summary arrives before the complete plan reference. Both documents come from the parent’s own plan.

When do they arrive?

Current enrollees must receive the ANOC by September 30 and the EOC by October 15.

October 15 is also the first day of Medicare Open Enrollment, which runs through December 7. During that window, an enrollee can make a coverage change for the following year.