Medicare Form CMS-L564, “Request for Employment Information,” is the document that proves you had group health coverage through a job so you can enroll in Part B without a late penalty. You fill out Section A, your employer fills out Section B, and you submit it together with Form CMS-40B — the actual Part B application — to your local Social Security office.1Centers for Medicare & Medicaid Services. CMS L564 – Medicare Request for Employment Information
Who Needs to File CMS-L564
File this form if you delayed Part B because you or your spouse had health coverage through an employer while actively working. That situation triggers a Special Enrollment Period giving you eight months to sign up for Part B after the employment or the group health plan coverage ends, whichever happens first.2Social Security Administration. Special Enrollment Period L564 is the proof that gets you into that window.
The coverage must have been based on current employment. COBRA continuation coverage and retiree health plans do not qualify, even when the insurance itself is identical to what you had while working. If you signed up for COBRA after leaving a job, your eight-month SEP clock started when your employment or employer-based coverage ended, not when COBRA runs out.3Medicare. Working Past 65 People who assume COBRA extends the window sometimes miss the deadline entirely.
Where to Get the Form
Download CMS-L564 as a PDF directly from the CMS website.1Centers for Medicare & Medicaid Services. CMS L564 – Medicare Request for Employment Information The Social Security Administration’s Part B sign-up page also links to it.4Social Security Administration. Sign Up for Part B Only Print and fill it out by hand, or type into the PDF fields before printing. Grab Form CMS-40B from the same pages while you’re there.
How to Fill Out Section A
Section A is your part. The fields are short:5Centers for Medicare & Medicaid Services. Medicare Request for Employment Information
- Applicant’s name — your full legal name.
- Applicant’s Social Security Number — your nine-digit SSN.
- Employee’s name — fill this in only if the employee whose job provided the coverage is someone other than you, such as your spouse.
- Employee’s SSN — same rule; only needed when the employee is a different person.
- Employer’s name and address — the company that provided the group health plan.
L564 does not ask for your Medicare Number. That goes on CMS-40B.6Centers for Medicare & Medicaid Services. Request for Enrollment in Medicare Part B (CMS-40B)
How to Get Section B Completed
Section B is the substance of the form, and an authorized company official — usually someone in HR or benefits — fills it out and signs. The questions cover:7Centers for Medicare & Medicaid Services. CMS-L564 Request for Employment Information – Section B
- Whether the applicant was covered under an employer group health plan.
- The date coverage began.
- Whether coverage has ended, and the end date if it has.
- Dates of employment, including whether the employee is still on the job.
- If the applicant is disabled and covered under a large group plan, the months the group plan was the primary payer.
- Whether coverage was through an hours bank arrangement and whether reserve hours remain.
- The company official’s signature, title, date, and phone number.
Hand the form to HR as early as you can. Federal retirees and employees enrolled in FEHB request a completed L564 from the Office of Personnel Management, which typically responds within three to five business days.8U.S. Office of Personnel Management. Request a Completed CMS L-564
If Your Employer Cannot Complete Section B
Companies close. HR contacts go quiet. If your employer is unable or unwilling to fill out Section B, complete it yourself as best you can and submit secondary evidence of your group coverage. Social Security accepts:9Social Security Administration. How to Apply for Medicare Part B During Your Special Enrollment Period
- Income tax returns showing health insurance premiums paid.
- W-2s reflecting pre-tax medical contributions.
- Pay stubs with 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 payment of health insurance premiums.
Gather records covering the entire period from when you first became Medicare-eligible through the end of your group coverage. More documentation means fewer follow-up questions from SSA.
Pairing L564 with CMS-40B
L564 by itself does not enroll you in Part B. You also need CMS-40B, the actual Part B enrollment application, and CMS instructions say to submit both forms together.1Centers for Medicare & Medicaid Services. CMS L564 – Medicare Request for Employment Information
CMS-40B collects your Medicare Number, mailing address, phone, and email. It asks whether an employer or insurer required you to enroll in Part B; if so, attach documentation. It also has a field where you pick your preferred coverage start date.6Centers for Medicare & Medicaid Services. Request for Enrollment in Medicare Part B (CMS-40B)
How to Submit the Forms
Send both completed forms to your local Social Security office by fax or mail. Find the office and its fax number at SSA.gov/locator.1Centers for Medicare & Medicaid Services. CMS L564 – Medicare Request for Employment Information You can also deliver them in person, which lets an SSA representative check that everything is filled out before you leave.
There is no online upload portal for these forms. The SSA’s Part B page directs applicants to fax or mail.4Social Security Administration. Sign Up for Part B Only If you mail, use a tracked service and keep copies.
When Your Part B Coverage Starts
The effective date depends on when in the eight-month SEP you file. Sign up while you are still covered under the employer plan, or during the first full month after coverage or employment ends, and you can choose your start date: the first of the month you enroll, or the first day of any of the three following months.9Social Security Administration. How to Apply for Medicare Part B During Your Special Enrollment Period
Enroll during any of the remaining seven months of the SEP and your coverage starts the first of the month after you sign up. Filing earlier in the window gives you more control over timing and avoids a gap between employer coverage ending and Part B beginning.
The Penalty This Form Prevents
The point of L564 is to avoid a penalty that lasts for life. Miss your enrollment windows and sign up later without a valid SEP, and Medicare adds 10 percent to your monthly premium for every full 12-month period you could have had Part B but did not.10Medicare. Avoid Late Enrollment Penalties The surcharge never goes away.
The standard Part B premium for 2026 is $202.90 per month.11Centers for Medicare & Medicaid Services. 2026 Medicare Parts A and B Premiums and Deductibles Three years without Part B and without a valid reason to delay would mean a 30 percent penalty, roughly $61 extra every month, riding on top of whatever the premium is each year going forward. Filing L564 with proof of employer coverage eliminates that surcharge by showing you had a legitimate reason to wait.
If Your Enrollment Is Denied
If Social Security decides you do not qualify for the SEP — for example, if they conclude your coverage was not based on current employment — you can appeal through your local Social Security office. When the denial resulted from a government error, misinformation from a federal employee, or other circumstances beyond your control, you may get the decision reversed and any penalty surcharge removed. File the appeal quickly and bring any additional documentation of your coverage history.
If the appeal fails, the fallback is the General Enrollment Period, which runs January 1 through March 31 each year, with coverage starting the following July 1. That gap, plus the permanent late penalty, is why getting L564 right the first time matters.