CMS-L564 Instructions: Section B and Filing Before Coverage Ends

What the CMS-L564 does and why you need it

Form CMS-L564 ("Request for Employment Information") documents group health plan coverage based on current employment for a Medicare Part B Special Enrollment Period (SEP). It has no field for an anticipated coverage end date. If the employee is still working and the plan is active, the employer marks "Yes" to "Is (or was) the applicant covered?", enters the coverage start month/year, marks "No" to "Did the coverage end?", leaves that date blank, enters the employee's actual work start month, leaves "To" blank, marks "Yes" to "Still employed?", and signs and dates the form. Do not enter a scheduled future date as if coverage had ended.

When applying through this SEP, you generally submit CMS-L564 with Form CMS-40B, the Part B enrollment application. The CMS-L564 instructions say coverage must have been through your or your spouse's current employment since the first month you were eligible for Part B, and must not have ended more than 8 months ago. For disability-based Medicare, the form also describes coverage through a large group health plan based on your, your spouse's, or a family member's current employment. Ask SSA about eligibility if your situation differs.

Section-by-section breakdown (03/2025 revision)

The CMS-L564 has two sections. Who fills out each one matters.

Section A — you complete this. It collects your name and Social Security number, the employee's name and SSN if different from yours (for example, if you're enrolling based on a spouse's employment), and the employer's name and address. That's it. Section A has no coverage dates, no Medicare number, and no group plan number.

Section B — your employer completes this. This is the section HR or the benefits administrator fills in. It has two parts:

Employer Group Health Plans:

• Whether you are (or were) covered under the employer group health plan (Yes/No)
• The month and year coverage started (mm/yyyy)
• Whether the coverage ended (Yes/No), and if yes, the date it ended (mm/yyyy)
• When the employee worked for the company: From and To dates (mm/yyyy), and whether the employee is still employed (Yes/No)
• For large group health plans with a disabled applicant: the months the plan was primary payer (From/To)

Hours Bank Arrangements:

• Whether you are (or were) covered under an hours bank arrangement (Yes/No)
• Whether you have hours left in reserve (Yes/No)
• The date reserve hours ended or will be used (mm/yyyy)

After both parts, a company official signs, provides the date signed (mm/dd/yyyy), their title, and phone number.

If more than one employer provided coverage during the period you are documenting, ask SSA whether it needs a separate form or other evidence for each coverage period.

Filling it out before coverage ends

When the employee is still working and coverage is active, the employer marks "Yes" to "Is (or was) the applicant covered?", enters the coverage start month/year, marks "No" to "Did the coverage end?", and leaves the coverage end date blank. For employment, enter the "From" month/year, leave "To" blank, mark "Yes" to "Still employed?", and sign/date the form; do not enter a future coverage end date.

Medicare.gov says you can apply while you or your spouse are still working and have job-based coverage. It advises signing up for Part B the month before retirement if you want it to start when job-based coverage ends; it says coverage starts the month after SSA receives the completed forms. SSA also says some people who apply while still covered, or during the first month after coverage ends, can request a Part B start month in the CMS-40B Remarks section. The effective-date rules depend on when you apply, so confirm the requested month with SSA and the employer plan.

The only "will" date on CMS-L564 is the hours-bank reserve date.

The forms give SSA time to review the request, but filing early does not guarantee there will be no coverage gap. Confirm the employer plan's end date and the Part B effective date with the employer and SSA.

When your employer refuses to sign

Companies get acquired, HR departments get restructured, or a benefits administrator doesn't want to deal with an unfamiliar form. Here's the process when Section B stays blank:

Put the request in writing. Send a letter or email to your employer's HR department requesting they complete Section B. Date it and keep proof of delivery.

Follow up and keep a record. Save a copy of your request and any response, then proceed with secondary evidence if the employer does not respond.

Ask SSA about secondary evidence. The CMS-40B instructions say to contact SSA if the employer is out of business or refuses to complete CMS-L564. SSA's instructions say that if the employer cannot complete Section B, fill it out as best you can and submit evidence of the coverage. SSA lists examples including:

• Income tax returns showing health insurance premiums paid
• W-2s reflecting pre-tax medical contributions
• Pay stubs showing health insurance premium deductions
• Health insurance cards with a policy effective date
• Explanations of benefits paid by the group health plan
• Statements or receipts showing health insurance premiums paid

These are examples of evidence to submit, not a guarantee that a particular document will establish SEP eligibility. Contact the local SSA office for guidance on what to send in your case.

When the employer is out of business

If the employer is closed, contact SSA about the evidence it can accept when the employer cannot complete Section B.

Gather relevant records that show both employment and group health plan coverage. If the company was acquired, ask the successor company whether it can provide employment or coverage records.

Filing the CMS-L564

CMS-L564 directs you to mail or fax the completed form with CMS-40B to your local Social Security office. SSA also describes an online Part B SEP application for some applicants; check SSA's current instructions to see whether that route applies to you. Find your local office at SSA.gov/locator.

SSA instructs applicants who can choose an effective date under the current-employment SEP rules to write "I want Part B coverage to begin (MM/YY)" in the CMS-40B "Remarks" section. This states the month you are requesting; SSA determines the effective date under the rules that apply to your filing.

Common mistakes that delay processing

Entering a future end date. If coverage is still active, the employer checks "No" on "Did the coverage end?" and leaves that end-date field blank. The form asks for an end date only when coverage has ended.

Treating COBRA as current-employment coverage. Medicare says COBRA does not count as coverage based on current employment for this SEP. Check with SSA about which employment and coverage dates to document.

Forgetting the CMS-40B. CMS-L564 documents employment information; CMS-40B is the Part B enrollment application. The CMS-L564 instructions say to submit the two forms together.

Waiting too long. The form says coverage must not have ended more than 8 months ago to use this SEP. If you may be near that limit, contact SSA promptly. If you think you missed the SEP, ask SSA whether another enrollment period or exception applies; a late-enrollment penalty may apply depending on your circumstances.

What happens after you file

SSA reviews your enrollment request and the evidence for SEP eligibility. It may ask for more information. Confirm the effective date in SSA's decision rather than assuming that the requested month has been approved.

If SSA denies your request, read the notice promptly and ask SSA about reconsideration. SSA generally gives 60 days to request reconsideration of a non-medical decision; Form SSA-561-U2 (Request for Reconsideration) is one way to request it. Follow the deadline and instructions in your notice.

The Medicare Late-Enrollment Penalties and Special Enrollment guide includes a CMS-L564 packet with pre-written employer request letters, a secondary evidence checklist, and a self-certification template for when employers won't cooperate.

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