Medicare with Parkinson's — the 24-month wait and the choices you can't easily undo

Medicare is the single biggest thing that changes about your finances after a Parkinson’s diagnosis in the United States. It is also the part people arrive at least prepared for, because most of the decisions come with deadlines attached and several of them are hard to reverse.

This page walks through the four parts, how you get there from a disability claim, and the specific places where waiting too long costs money. Everything was checked against Medicare’s own pages in August 2026. The dollar figures are 2026 calendar-year figures and change every January.

The four parts, and which two you actually choose

Medicare is not one policy. It is four letters that combine in two different ways.

Two of those four are automatic once you qualify. The choices you make are: Original Medicare (A + B) plus a separate Part D plan, optionally with a Medigap policy — or a Medicare Advantage plan that bundles it all.

That fork matters more with Parkinson’s than it does for most conditions, because of one line on Medicare’s own costs page:

There’s no yearly limit on what you pay out-of-pocket, unless you have supplemental coverage, like a Medicare Supplement Insurance (Medigap) policy, or you join a Medicare Advantage Plan.

Original Medicare on its own has no ceiling. Twenty percent of a neurologist visit is small. Twenty percent of a deep brain stimulationDeep brain stimulation — a surgical treatment in which electrodes placed in the brain are connected to a pulse generator implanted in the chest.Learn more procedure, or of a year of physical and speech therapy, is not. Something has to sit on top of Part B, and the two candidates are Medigap and Medicare Advantage.

If you got here through SSDI, the clock starts later than you think

Medicare’s rule is short. In Medicare’s own words:

If you’re getting Social Security disability benefits, you’ll get Medicare automatically after getting disability benefits for 24 months.

Elsewhere Medicare adds the part that saves some people two years of waiting: you get Medicare after 24 months of disability benefits “or when you turn 65 – whichever comes first.” If you were diagnosed at 64, you are not waiting until 66.

The trap is what “24 months of disability benefits” is measured from. It is not your diagnosis and it is not the date you applied. Social Security’s own wording is precise about the starting line:

We’ll automatically enroll you in Medicare 2 years after the date you became entitled to Disability.

Entitlement is not the same as onset. Social Security applies a cash waiting period first, so your first payment arrives some months after the date it finds your disability began — the detail is on our page about what listing 11.06 actually asks for. Stack the waiting period and the 24 months and you are well over two years past your established onset date before a Medicare card arrives.

There is one exception, and it is worth knowing precisely because Parkinson’s does not get it. In Social Security’s words, “if you have ALS (Lou Gehrig’s disease), you can get Medicare as soon as you become entitled to Disability.” Parkinsonian syndromes have no such shortcut.

What to do during the gap — and the COBRA extension built for it

Two and a half years without coverage is not a plan. Three routes exist, and one of them looks like it was designed around this exact wait.

COBRA, extended by 11 months. If you had employer coverage and left the job or dropped below full hours, COBRA normally lasts 18 months. The Department of Labor spells out an extension most people never hear about:

If any qualified beneficiary in your family is disabled and meets certain requirements, all qualified beneficiaries may receive an 11-month extension of COBRA coverage—for a total of up to 29 months.

Twenty-nine months. That is not a coincidence — it is the length of the Medicare wait. Two conditions attach. Social Security must determine that you are disabled before the 60th day of COBRA coverage, and the disability has to continue through the initial 18 months. You also have to tell the plan about the SSA determination; the plan sets the deadline, but it cannot be shorter than 60 days from the determination. During the extension the plan may charge up to 150% of the premium rather than the usual 102%.

The practical consequence: if you are on COBRA and an SSDI decision is pending, that decision letter is time-sensitive in a second way that nobody tells you about. Put a reminder in the calendar for day 50 of your COBRA coverage.

The Health Insurance Marketplace. Losing job-based coverage opens a special enrollment period, and you have 60 days from the loss to pick a plan at HealthCare.gov. Tax credits and cost-sharing reductions may bring the premium well below COBRA’s.

Medicaid. If your income has dropped, Medicaid enrollment is open year-round rather than seasonal, and it is worth checking even if you assume you earn too much — the thresholds vary a great deal by state.

Medigap: one window, and for under-65s it opens at 65

This is the single most expensive thing to get wrong.

Medigap policies are standardized and sold by letter — Plan G, Plan K and so on — so the same letter buys the same benefits whichever company sells it. What is not standardized is whether a company will sell you one at all.

Federal law gives you a six-month Medigap Open Enrollment Period, and Medicare’s description of it contains a condition that catches people who came in through disability:

Under federal law, you get a 6 month Medigap Open Enrollment Period. It starts the first month you have Medicare Part B and you’re 65 or older.

Read that twice if you are under 65. Your Part B started, but your Medigap window did not. Medicare is explicit about what that means:

If you’re under 65 and have Medicare because of a disability or ESRD, you might not be able to buy a Medigap policy until you turn 65. Federal law generally doesn’t require insurance companies to sell Medigap policies to people under 65. However, in some states insurance companies do offer Medigap policies to people under 65.

So there are two things to do. First, call your state insurance department — a good number of states require insurers to offer Medigap under 65, and this is purely a matter of where you live. Second, mark the month you turn 65 in your calendar now. That is when your one-time six-month window opens, and during it no insurer can refuse you, charge you more, or make you wait because of Parkinson’s. Miss it and, in Medicare’s words, “you may have to pay more for a policy,” “fewer policy options may be available,” and “the insurance company is allowed to deny you a policy if you don’t meet their medical underwriting requirements.”

A progressive condition is precisely what medical underwriting screens out. The window does not reopen.

Medicare Advantage: the questions to ask before you sign

Medicare Advantage is the other way to get a spending ceiling, and for some people it is clearly the better deal — it caps out-of-pocket costs, usually bundles Part D, and often adds dental, vision and hearing. But the trade-offs land in specific places with Parkinson’s.

• Is your movement disorder specialist in the network? Parkinson’s care is a small specialty. A plan whose network covers your city may still not cover the one clinic you want.
• Does the plan require prior authorization for therapy? Physical, occupational and speech therapy are ongoing needs, not one-off events, and Medicare notes you “may need to get approval for certain drugs or services before you get them.”
• What are the copays for durable medical equipment? Walkers, wheelchairs and hospital beds run through Part B, and plans price the member’s share differently.
• Does the drug list cover your exact regimen? Not “Parkinson’s drugs” — the specific formulations you take, at the doses you take.
• Can you get out later? Switching from Medicare Advantage back to Original Medicare is allowed, but buying a Medigap policy at that point may require underwriting unless you have a guaranteed issue right. Ask about this before you join, not after.

Part D is not a detail when the prescriptions are permanent

Levodopa, dopamine agonists, MAO-B inhibitorsMonoamine oxidase B inhibitors — drugs that slow the breakdown of dopamine in the brain, often used alongside or before levodopa.Learn more and the drugs used for sleep, mood and blood pressure add up to a list you will refill every month for decades. Three figures decide what that costs.

The $2,100 cap. Once your out-of-pocket spending on covered Part D drugs reaches $2,100 in 2026, you move into the catastrophic stage and, in Medicare’s words, “you won’t have to pay out-of-pocket for covered Part D drugs for the rest of the calendar year.” The cap resets every January.

Your plan’s formulary. The cap only counts covered drugs. A drug your plan does not list, or lists on a high tier, is the thing that breaks the budget — and formularies change annually.

The late enrollment penalty. Skip Part D when you are first eligible and go 63 days or more without creditable drug coveragePrescription drug coverage that is expected to pay, on average, at least as much as Medicare drug coverage — for example from a current or former employer, TRICARE, the VA, or the Indian Health Service.Learn more, and you pay 1% extra for every month you went without, for as long as you have Part D. It never expires.

If your income is limited, Extra Help changes the arithmetic completely. In 2026 the limits are $23,940 in income and $18,090 in resources for an individual, $32,460 and $36,100 for a married couple. If you qualify you pay a $0 premium, a $0 deductible, and no more than $5.10 for a generic or $12.65 for a brand-name drug. People with full Medicaid, an SSI payment, or help from a Medicare Savings Program get Extra Help automatically. Everyone else applies through Social Security, and a SHIP counselor will do it with you for free.

The dates worth keeping

Special Enrollment Periods sit outside all of this and cover life events — moving, losing other coverage, getting Medicaid, or qualifying for Extra Help. If something changes, ask whether it opened a window before you assume you have to wait for October.

Get free help rather than guessing

Every state runs a State Health Insurance Assistance Program (SHIP). Medicare describes SHIP counseling as free and personalized, and notes that SHIPs “aren’t connected to any insurance company or health plan.” That last part is the point: a broker earns a commission on what you buy, and a SHIP counselor does not.

Two hours with a SHIP counselor, with your actual prescription list in hand, will answer the Medigap and Advantage questions above better than any comparison website. Find yours at shiphelp.org, or call 1-800-MEDICARE.

If this applies to you

This page explains how Medicare works; it does not decide your coverage or recommend a plan. Figures are 2026 calendar-year figures checked in August 2026 and change each January. Confirm your own position with 1-800-MEDICARE or a SHIP counselor before you enroll in anything.