How to Reinstate Medicare Part B: Forms, Cost, and Appeals

To reinstate Medicare Part B, submit Form CMS-40B to the Social Security Administration during a qualifying enrollment window, pay any premiums you owe, and accept any late enrollment penalty that applies. The standard Part B premium for 2026 is $202.90 per month, and the penalty adds 10% for every full 12-month period you were eligible but not enrolled.¹ The exact path depends on why your coverage ended and how long ago it lapsed.

When You Can Sign Back Up

You cannot re-enroll whenever you want. Federal law limits Part B enrollment to specific windows, and the one you fall into determines both your coverage start date and whether you owe a penalty.

General Enrollment Period

If nothing special applies to your situation, you sign up between January 1 and March 31 each year.² Coverage begins the month after you enroll.³ Miss this window and you generally wait until the next January. Enrolling this way usually triggers the lifelong late enrollment penalty.

Special Enrollment Period

You qualify for a Special Enrollment Period if you delayed or dropped Part B while you or your spouse had health insurance through current employment. You can enroll any time the employment continues, or during the eight months after the job or the employer coverage ends, whichever comes first. Signing up in this window avoids the late enrollment penalty.

COBRA does not extend this period. The eight-month clock starts when active employment ends, even if you elect COBRA afterward.⁴

Narrower Special Enrollment Periods also exist. People released from incarceration who missed their initial enrollment have 12 months from release to enroll, and people who lost Medicaid coverage on or after January 1, 2023, and missed a Medicare enrollment period may qualify as well.⁵

Forms to File

The core document is Form CMS-40B, the Application for Enrollment in Medicare Part B. It asks for your Medicare number, your full name as it appears on your Social Security record, and your signature. In the remarks section, note that you previously had Part B and are requesting re-enrollment. Print or type clearly; illegible entries slow processing.⁶

If you are enrolling under a Special Enrollment Period based on employer coverage, you also need Form CMS-L564, the Request for Employment Information. Fill out Section A and give the form to your employer, whose human resources or benefits officer completes Section B to certify your dates of group health coverage. Submit both forms together.⁷

If the employer is out of business or otherwise cannot complete the form, gather pay stubs, W-2s, or tax returns showing you had active employment and group coverage during the relevant period. Those records can serve as alternative proof.

How to Submit the Application

Social Security accepts your paperwork several ways:

Online, through SSA’s Part B sign-up tool if you already have Part A.⁸
By fax or mail to your local Social Security office. If you mail it, use certified mail so you have proof of the date you sent it.⁹
By uploading scanned documents through SSA’s online portal.¹⁰
In person at your local Social Security field office.

SSA will send a written notice approving or denying enrollment. If approved under the General Enrollment Period, coverage starts the month after you sign up. Under a Special Enrollment Period, it can start as early as the first of the month you enrolled.

If You Missed the Window Because of Circumstances Beyond Your Control

SSA can restore coverage outside the standard windows in limited cases. The two main routes are good cause and equitable relief.

Good cause applies when the reason you did not pay or enroll on time was something you could not control or reasonably guard against, weighed against your health, education, and personal circumstances.¹¹ Common examples:

You were too ill or incapacitated to act, and no one was handling your affairs.
Billing or termination notices were misaddressed and never reached you.
An unavoidable, unexpected financial crisis prevented payment.
You had a good-faith basis for believing the payment had already been made.

To pursue good cause, send SSA a written statement describing what happened and why you could not act on time. Attach supporting documents: medical records, copies of returned or misaddressed mail, or financial records showing the emergency. An adjudicator reviews the file and decides whether to waive the deadline.

Equitable relief is a separate remedy for when SSA itself caused the problem by failing to process your enrollment on time. If SSA’s delay leaves you owing six or more months of back premiums, the agency can adjust your coverage start date and set up an installment plan.¹² Federal regulations also allow enrollment rights to be restored when a government representative gave you incorrect or incomplete information that caused you to miss an enrollment opportunity.¹³

What Reinstatement Will Cost

Most people pay the standard 2026 premium of $202.90 per month. The annual Part B deductible for 2026 is $283; after you meet it, Part B typically pays 80% of approved charges and you pay the remaining 20%.¹

If you went 12 or more consecutive months without Part B and without qualifying employer coverage during that time, expect a late enrollment penalty. The penalty adds 10% to your monthly premium for each full 12-month period you were eligible but not enrolled, and it lasts as long as you have Part B.¹⁴ Two full years without coverage means a 20% surcharge — roughly $40.58 added to the 2026 premium every month, for life.

Higher-income beneficiaries pay an Income-Related Monthly Adjustment Amount on top of the standard premium. For an individual filer with modified adjusted gross income of $109,000 or less, there is no surcharge; above that, the surcharge climbs in tiers to $487.00 for income of $500,000 or more, producing a total monthly premium of $689.90 at the top bracket. Joint filers have higher thresholds, and married individuals filing separately face a steeper bracket structure with fewer tiers.¹

If SSA backdates your coverage under equitable relief, you may owe premiums for the retroactive months. You can pay a lump sum, have the amount withheld from your monthly benefit, or set up installments.¹²

If Your Application Is Denied

You have 60 days from the denial notice to file a Request for Reconsideration using Form SSA-561-U2.¹⁵ From there, the Medicare appeals process has up to five levels: redetermination, reconsideration by a Qualified Independent Contractor, a hearing before an Administrative Law Judge, review by the Medicare Appeals Council, and judicial review in federal district court. You generally have 60 days from each decision to move to the next level, and the higher levels carry minimum amount-in-dispute thresholds.¹⁶ Keep copies of everything you file and every notice you receive.

Help Paying the Premium

If the cost is a hardship, a Medicare Savings Program run by your state may cover it. The Qualified Medicare Beneficiary program pays your Part B premium, deductible, and coinsurance. For 2026, you may qualify with monthly income at or below $1,350 (individual) or $1,824 (couple) and countable resources no higher than $9,950 (individual) or $14,910 (couple). Alaska and Hawaii use slightly higher income limits, and some states set more generous thresholds than the federal minimums. Contact your state Medicaid office to apply.¹⁷

Enrolling in a Medicare Savings Program also eliminates the late enrollment penalty, which matters if you are reinstating after a long gap.¹⁴

1
Centers for Medicare & Medicaid Services. 2026 Medicare Parts A and B Premiums and Deductibles
2
Medicare. When Does Medicare Coverage Start? – Section: Between January 1-March 31 Each Year (General Enrollment Period)
3
Social Security Administration. Plan for Medicare – When to Sign Up for Medicare – Section: When You Miss the Other Periods
4
Medicare. When Can I Sign Up for Medicare?
5
Centers for Medicare & Medicaid Services. Original Medicare (Part A and B) Eligibility and Enrollment
6
Centers for Medicare & Medicaid Services. Application for Enrollment in Medicare Part B (Medical Insurance)
7
Centers for Medicare & Medicaid Services. Form CMS-L564 Request for Employment Information
8
Social Security Administration. Sign Up for Medicare
9
Medicare. Ready to Sign Up for Part A and Part B
10
Social Security Administration. Upload Documents
11
Social Security Administration. POMS HI 01001.360 – Good Cause Defined
12
Social Security Administration. POMS HI 00805.195 – Enrollment Not Processed Timely
13
eCFR. 42 CFR 407.32 – Prejudice to Enrollment Rights Because of Federal Government Misrepresentation, Inaction, or Error
14
Medicare. Avoid Late Enrollment Penalties
15
Social Security Administration. Request Reconsideration
16
Medicare. Appeals in Original Medicare
17
Medicare. Medicare Savings Programs