CMS-40B PDF Form & Guide

Quick answer

What is CMS-40B used for?

This form supports a Medicare enrollment, coverage, or cost decision listed by SSA. Part A, Part B, prescription-drug assistance, and income-related premium matters use different evidence and timing rules.

An application starts or expands a claim. Complete every eligibility section that applies, preserve the filing date, and avoid treating an application as approval of the requested benefit.

For CMS-40B, the transaction named by the government is “Application for Enrollment in Medicare - Part B (Medical Insurance).” Use that title to distinguish this PDF from forms that collect related facts but produce a different agency action.

What to prepare before filling CMS-40B

01
Confirm that CMS-40B — Application for Enrollment in Medicare - Part B (Medical Insurance) — matches the action described in your SSA, CMS, or IRS notice. Similar form numbers may serve different programs or review stages.
02
Collect the Medicare card or number, employment and group-health-plan dates, coverage notices, tax or income evidence, and the life event or enrollment-period documents relevant to the request.
03
Download a fresh copy of CMS-40B from the official link below. SSA warns that browser PDF viewers may not fill forms consistently, so save the PDF and use current Adobe Reader when needed.
04
Write names, Social Security or claim numbers, dates, addresses, and amounts exactly as they appear in the records you are using. Mark nonapplicable items as the instructions direct instead of inventing an answer.
05
Review CMS-40B for signatures, dates, attachments, continuation pages, and any case-specific return instructions. Keep a complete copy and delivery record.

Questions specific to “Application for Enrollment in Medicare - Part B (Medical Insurance)”

Use these prompts to test whether your records actually support the subjects named in the official CMS-40B title.

Before signing, can you independently recheck every date, amount, relationship, or identifier connected with “application” rather than relying on the working draft?
Is “enrollment” a current fact, a historical fact, or an estimate here, and have you labeled that distinction wherever CMS-40B allows?
Before signing, can you independently recheck every date, amount, relationship, or identifier connected with “medicare” rather than relying on the working draft?
What definition or instruction controls “part” in this filing, and have you avoided substituting the everyday meaning for the program-specific question?
Would an attachment about “medical” make the answer clearer, and if so, does it identify CMS-40B, the relevant person, and the question it supports?
For the “insurance” part of CMS-40B, which dated record supports the answer, and does that record cover the full period requested by the PDF?

Evidence review

Collect the Medicare card or number, employment and group-health-plan dates, coverage notices, tax or income evidence, and the life event or enrollment-period documents relevant to the request.

Before you sign

Check the coverage component and requested effective or termination date carefully. Ending or delaying coverage can create gaps, penalties, or limited re-enrollment options, so use current Medicare guidance.

A reliable way to complete CMS-40B

Map the source records

Separate documents into identity, program, financial, and supporting-evidence groups. Label multi-page records and note any page that contains the value you plan to enter. Work from those groups instead of memory. If another person supplies information, record that person’s name and basis of knowledge so you can distinguish firsthand facts from reported facts.

Review fields and branches

If an answer is estimated, say so in the manner the form permits and document how you reached it. Choose a reasonable source such as a calendar, statement, or employer record, not an unsupported guess. When an exact value later becomes available, determine whether the agency requires an update rather than silently changing your retained copy.

Package and track the filing

Before sending, simulate an intake review. Confirm that the correct edition opens, pages are in order, barcodes and margins are unobstructed, required attachments are readable, and signatures use an accepted method. Reopen the saved PDF on another device when practical to ensure typed entries were actually retained.

Official CMS-40B PDF and resources

These government links were verified in the SSA forms directory on 2026-08-09. Download a fresh PDF before filing because agencies can revise forms and instructions.

English CMS-40B PDF Official form information Spanish PDF

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Prepare CMS-40B from your records

Add the blank government PDF and your source documents. Clerks AI can map supported facts to fields and flag gaps for review. You remain responsible for eligibility, signatures, accuracy, evidence, and submission.

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CMS-40B FAQ

Is CMS-40B free to download?

Yes. SSA says all forms in its official directory are free. Use the government PDF link on this page; do not pay a third party merely for the blank form.

Can I fill CMS-40B in a web browser?

Possibly, but SSA says browser PDF viewers do not work consistently for filling or screen reading. Download the file and use current Adobe Reader if fields, saving, or accessibility features do not work correctly.

Where do I submit CMS-40B?

Follow the address, office, upload route, or case-specific instruction in the PDF and any notice you received. The SSA directory says paper forms may generally be mailed or faxed unless the form states otherwise, but not every form uses the same destination.

Related medicare forms

CMS-1763

CMS-40B: Application for Enrollment in Medicare - Part B (Medical Insurance)