# CMS-40B form: fill out and sign online, free

> Form CMS-40B is the Centers for Medicare & Medicaid Services's "Request for Enrollment in Medicare Part B (Medical Insurance)." In its words: "Use this form if you already have Medicare Part A and want to sign up for Part B (Medical Insurance)." (CMS, Form CMS-40B (07/2025), page 1)

Page: https://pdfinish.com/forms/cms-40b
Last updated: November 1, 2026

## CMS-40B at a glance

- **Agency:** Centers for Medicare & Medicaid Services (CMS)
- **What it is for:** Use this form if you already have Medicare Part A and want to sign up for Part B (Medical Insurance).
- **Who fills it:** In the form’s words: “Use this form if you already have Medicare Part A and want to sign up for Part B (Medical Insurance).” It also says: “If you don’t have Part A, don’t complete this application. Contact Social Security to apply for Medicare for the first time.”
- **Who it goes to:** “Mail or fax your completed, signed form to your local Social Security office. Find an office near you at SSA.gov/locator.” (printed on the form)
- **Signature:** Section 3 of the form is “Signature(s)”: a “Signature of applicant” line with the date signed. If the form is signed by mark (X), a witness who knows the person applying must also sign.
- **Revision:** 07/2025
- **Last checked:** November 1, 2026
- **Official form (PDF):** https://www.cms.gov/Medicare/CMS-Forms/CMS-Forms/downloads/cms40b-e.pdf
- **Official instructions:** https://www.cms.gov/Medicare/CMS-Forms/CMS-Forms/downloads/cms40b-e.pdf

## What the agency says

- The form says you can use it to sign up for Part B “During your Initial Enrollment Period,” “During the General Enrollment Period from January 1–March 31 each year,” and “If you’re eligible for a Special Enrollment Period.” (Source: [CMS, Form CMS-40B (07/2025), page 1](https://www.cms.gov/Medicare/CMS-Forms/CMS-Forms/downloads/cms40b-e.pdf))
- For the employment questions the form says: “Have your employer fill out the form CMS-L564 (Request for Employment Information) and return it with your application.” (Source: [CMS, Form CMS-40B (07/2025), page 2](https://www.cms.gov/Medicare/CMS-Forms/CMS-Forms/downloads/cms40b-e.pdf))

## How to fill it out

1. **Open the form.** Press Fill it now. The form opens in Finish PDF in your browser. Nothing is uploaded.
2. **Type in the boxes.** Click a box and type, or tick a checkbox. Add your signature in the Sign step and press Lock to put your entries into the page.
3. **Save your copy.** Name the file and download it. Your original blank form is never changed.

## Common questions

### Is there a 2026 CMS-40B?

CMS does not put a year in the form’s name. The file CMS publishes at the address below is marked “CMS-40B (07/2025)” and “Expires: 07/31/2028” (OMB No. 0938-1230). This page carries that file, which we compared with CMS’s copy on November 1, 2026: https://www.cms.gov/Medicare/CMS-Forms/CMS-Forms/downloads/cms40b-e.pdf.

### Is the CMS-40B form free to fill out here?

Free to start. Your 2 free uses in total need no account. Filling in a form and signing it are free; the file you download counts as one of your free uses. After that, start your 7-day free trial of Pro or buy Pro for $2.99 a month.

### Is my information uploaded?

No. The form is filled in your browser and never uploaded, so what you type, including any Social Security number or other tax ID, stays on your device. We do not record what you type.

### Is this the latest version of Form CMS-40B?

It is the version the agency listed as current when we last checked on 2026-11-01: 07/2025. We compare our copy with the agency's every week. If the agency updates the form, this page says so and points to the official link until we update ours.

### Can I sign the CMS-40B electronically?

Whether an electronic signature is accepted is up to whoever asked you for the form, unless the agency says otherwise. Check the agency's instructions at https://www.cms.gov/Medicare/CMS-Forms/CMS-Forms/downloads/cms40b-e.pdf. PDFinish places a picture of your signature on the page; it is not a certificate-based digital signature.

### Where do I send the CMS-40B?

In the agency's words: “Mail or fax your completed, signed form to your local Social Security office. Find an office near you at SSA.gov/locator.” (printed on the form) Read the agency's instructions at https://www.cms.gov/Medicare/CMS-Forms/CMS-Forms/downloads/cms40b-e.pdf.

### What do I put in each box of the CMS-40B?

We do not tell you what to enter. The agency's own instructions explain each line: https://www.cms.gov/Medicare/CMS-Forms/CMS-Forms/downloads/cms40b-e.pdf.

## Related forms

- [Form CMS-L564](https://pdfinish.com/forms/cms-l564): CMS-L564 form
- [Form 8962](https://pdfinish.com/forms/8962): 8962 form

Also searched as: CMS-40B, CMS 40B form, Request for Enrollment in Medicare Part B, Medicare Part B enrollment form, Application for Enrollment in Medicare Part B.

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