Medicare 2026

Helping a Parent Enroll in Medicare: Who Can Sign, and How It Works

Helping an aging parent, spouse, or other loved one sort out Medicare can feel like a lot. One of the first questions families ask is a practical one: can I actually sign them up, or do they have to do it themselves? The short answer is that the person on Medicare is the one who signs — but if they truly can't, someone with the right legal authority can sign on their behalf. Here's how that works at the national level, and what to have ready before you call a plan or hit "Enroll Now" online.

The basic rule: the enrollee signs

Under CMS's Medicare Advantage and Part D enrollment guidance, a plan can accept an enrollment or disenrollment request from the eligible person or from that person's authorized representative recognized under state law. In plain terms, Mom or Dad fills out and signs the request. Only if they cannot do it themselves does an authorized representative sign for them.

"Sign" is flexible. On a paper form, it's a pen-and-ink signature. Over the phone, a verbal attestation of intent to enroll satisfies the signature requirement. Online, an electronic signature — or a clear "Enroll Now" or "I Agree" step — counts, and CMS treats electronic signatures as having the same legal effect as handwritten ones.

Who counts as an "authorized representative"

CMS gives examples of who may act for someone who cannot act for themselves:

• A court-appointed legal guardian.
• A person holding a durable power of attorney for health care decisions.
• A person authorized to make health care decisions under a state surrogate consent law.

The common thread is that the authority must come from state law and must cover health care decisions for that person. A friend, neighbor, or adult child who is simply "helping out" does not automatically qualify.

Importantly, being someone's Social Security representative payee — the person who receives and manages their Social Security checks — is not, by itself, enough to enroll them in a Medicare Advantage or Part D plan. Payee status covers benefit payments, not health care decisions.

What a representative has to do at enrollment

When someone other than the beneficiary completes the enrollment or disenrollment request, that person must:

• Attest that they have authority under state law to act for the beneficiary.
• Sign the form (or otherwise indicate their relationship to the person) and provide their contact information.
• Confirm that proof of their authority — guardianship papers, a durable power of attorney, or other state-required authorization — is available and can be produced if the plan or CMS asks to see it.

The plan should also ask a practical question: should plan materials and required notices go to the enrollee, to the representative, or to both? It's worth thinking about this in advance. Many families want copies to go to both addresses so nothing important gets missed.

CMS's current Medicare Advantage and Part D Enrollment and Disenrollment Guidance was most recently updated September 15, 2026, and applies to enrollments with an effective date on or after January 1, 2027.

Enrollment windows to keep in mind

The main window families use is Annual Enrollment (also called Open Enrollment): October 15 – December 7, 2026, with choices taking effect January 1, 2027. Someone newly eligible for Medicare has their own Initial Enrollment Period around their 65th birthday or their 25th month of disability benefits.

If your parent has Medicaid or qualifies for Extra Help with Part D costs, there's a monthly Special Enrollment Period that, since 2025, lets them move to Original Medicare with a stand-alone Part D plan, or switch stand-alone Part D plans. Full-benefit dual-eligible individuals (people with both Medicare and full Medicaid) can also join an integrated Dual Eligible Special Needs Plan (D-SNP) in any month.

A few numbers worth knowing for 2027

• The Part D out-of-pocket cap in 2027 is $2,400 (up from $2,100 in 2026). Once a plan member's out-of-pocket drug spending hits that cap, they pay $0 for covered Part D drugs the rest of the year.
• The most any Part D plan may charge as a deductible in 2027 is $700; many plans charge less, and specifics vary.
• The Part D base beneficiary premium for 2027 is $41.33 — a national figure used to calculate the late-enrollment penalty, not what any particular plan charges.
• Social Security announced a 3.6% cost-of-living adjustment for benefits payable beginning January 2027.

The 2027 Part B standard premium and deductible, and the 2027 IRMAA (income-related) surcharge brackets, have not yet been announced; CMS typically releases those figures in the fall.

Original Medicare + Medigap vs. Medicare Advantage: a neutral note

Families often ask which path is "better" for a parent. Both have real trade-offs. Original Medicare paired with a stand-alone Part D plan and, often, a Medigap policy generally offers broad provider access nationwide and more predictable out-of-pocket costs after premiums, but Medigap medical underwriting rules outside of initial eligibility vary by state. Medicare Advantage plans often bundle drug coverage and may include extras, but typically use provider networks and prior authorization. Neither is right for everyone — the honest answer depends on your parent's doctors, medications, budget, travel habits, and preferences.

Practical next steps

Before you sit down to enroll on someone's behalf, gather: the Medicare number, a list of current medications and preferred pharmacies, a list of doctors, and your proof-of-authority documents (guardianship order, durable power of attorney, or state-recognized surrogate authorization).

For official information, plan comparisons in your parent's area, and personalized help, go to Medicare.gov or call 1-800-MEDICARE (1-800-633-4227), available 24/7.

This article is for general education only. It is not affiliated with or endorsed by the federal government or any plan, and it does not rank, recommend, or compare specific plans.