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Form CMS-L564: Employer verification for Medicare Part B
Complete CMS-L564 for a Medicare Special Enrollment Period. The applicant fills Section A, the employer fills Section B, and both forms go to SSA.
At a glance
CMS-L564 documents employment information
CMS-L564 is the Medicare Request for Employment Information. The current revision is 03/2025. It is used to show group health plan coverage based on current employment for a Medicare Special Enrollment Period.
The form says the applicant must have had group health plan coverage through the applicant's or spouse's current employment since the first month the applicant was eligible for Medicare Part B, and that the coverage must not have ended more than eight months ago. A separate rule on the form applies to people who qualify for Medicare because of a disability.
Complete each section with the right person
Applicant completes Section A.
Enter the applicant's name and Social Security number, the employee's name and Social Security number if different, and the employer's name and address.
Employer completes Section B.
The employer answers the group health plan questions, enters the requested coverage and employment dates, and completes any applicable large-group-plan or Hours Bank fields.
Company official signs Section B.
The company official provides a signature, date, title, and phone number in the fields shown on the form.
Applicant submits both forms to SSA.
Mail or fax the completed CMS-L564 together with CMS-40B to the local Social Security office. Use the SSA office locator for the current destination.
What each form does
| Form | Purpose and completion |
|---|---|
| CMS-L564 | Documents employment and group health plan information; applicant completes Section A and employer completes Section B |
| CMS-40B | Requests enrollment in Medicare Part B; applicant completes and signs Sections 1 through 3 |
The current CMS-L564 instructions say to submit it together with CMS-40B to the local Social Security office by mail or fax.
Resolve missing employer information with SSA
If the employer cannot or will not complete Section B, contact Social Security for instructions about acceptable evidence for your case. Do not substitute a document list from a third-party guide, because Social Security decides what it needs to evaluate the request.
Check the form revision and instructions again before submission. Social Security decides Special Enrollment Period eligibility and may request more information.
Privacy boundary for IRIS
CMS-L564 requests Social Security numbers, which are government identifiers. Without an applicable written agreement with IRIS, do not submit a form containing a government identifier or highly sensitive medical record through IRIS. Mail or fax this form directly to Social Security instead.
Sources and current instructions
Review the linked source when a mailing depends on current USPS, agency, contractual, or legal requirements.
Use the current official CMS-L564.
Download the 03/2025 form, have the employer complete Section B, and submit it with CMS-40B directly to SSA.
How to file Social Security Form CMS-40B for Medicare Part B
Use the current CMS-40B to request Medicare Part B, complete its three sections, and submit the signed form to your local SSA office by mail or fax.
Read the guide
CMS-408 is not a current Medicare form
There is no current Medicare form CMS-408. Choose CMS-40B to enroll, CMS-L564 for employment information, or CMS-1763 to end coverage through SSA.
Read the guide
How to prepare and mail official paper forms
Prepare official forms for mailing by checking the issuer's current signature, attachment, address, deadline, and submission instructions before sending.
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