Medicare Open Enrollment: A Prescott Retiree's Checklist

Every fall, about the time the cottonwoods along Granite Creek start to turn, my patients begin bringing me their mail. Stacks of it. Glossy envelopes promising dental, vision, a gym membership and money back in the Social Security check. Then most people do nothing, which is what most of the country does: nearly 7 in 10 Medicare beneficiaries did not compare their coverage against other options during Open Enrollment (KFF).

This year's window is for plan year 2027. It opens Wednesday, October 15, 2026 and closes Sunday, December 7, 2026. Anything you change takes effect January 1, 2027.

I write some version of this every October, and not because switching is usually the right answer. I write it because one particular switch is far easier to make than to undo, and no mailer will tell you that. This article covers the window only: the dates, what you can change, and the traps. How direct primary care fits alongside Medicare is a separate article.

Key Takeaways

• Medicare Open Enrollment runs October 15 through December 7, 2026. Changes take effect January 1, 2027.
• Moving into Medicare Advantage is guaranteed. Moving back to Original Medicare with a Medigap policy is not, because Arizona follows only the federal minimum protections and medical underwriting applies.
• The January 1 to March 31 window is only for people already in a Medicare Advantage plan, and it allows one change.
• For 2027, the standard Part D deductible is $700 and the out-of-pocket cap is $2,400 (CMS).
• Free, unbiased Yavapai County counseling: NACOG at 928-251-0776.

When is Medicare Open Enrollment for 2027, and what is that second window in January?

Medicare Open Enrollment runs October 15 through December 7, 2026, and everything you change takes effect January 1, 2027. A second window, Medicare Advantage Open Enrollment, runs January 1 through March 31, 2027, but only if you are already enrolled in a Medicare Advantage plan on January 1 (Arizona SHIP).

That January window is narrower than most people assume. It allows exactly one change. You can move to a different Medicare Advantage plan, or drop Medicare Advantage and return to Original Medicare with a standalone drug plan. You cannot use it to join Medicare Advantage for the first time, and if you are in Original Medicare you cannot use it to switch drug plans (KFF).

So the fall window is the one that counts. Don't wait for the last week. If you enroll on December 6 and the plan needs one more document, you have a day to produce it. Have your decision made by Thanksgiving and a confirmation number written down before December.

Why is Medicare Open Enrollment a one-way door?

Because the two directions are not equal. Moving from Original Medicare into a Medicare Advantage plan is guaranteed during this window. Moving back later, with a Medigap policy covering what Original Medicare does not, may be impossible. KFF estimates 90% of Medicare Advantage enrollees age 65 and older, roughly 22.4 million people, have no guaranteed issue protection (KFF).

Here is the part almost nobody is told. Medigap has no annual open enrollment. Your protected chance comes once. Arizona SHIP states it plainly: “When you are 65 or older, starting on the first of the month that your Part B coverage begins you have a guaranteed issue right for six months.” After that, “If you are not eligible for guaranteed issue, you must submit to medical underwriting.”

Underwriting is not a formality. The same Arizona SHIP Medigap booklet warns that “Underwriting results could mean higher premiums, delayed coverage or the inability to buy their plan.” Then it says the quiet part out loud.

“The bottom line: if you want to change plans in the future, there is no guarantee that you will be able to do so.”

Arizona SHIP, 2026 Medigap Booklet

One mechanical detail people miss: “A Medigap policy cannot be used with a Medicare Advantage plan; it is only for beneficiaries with Original Medicare.” Enroll in Medicare Advantage and the Medigap policy goes away. Buying a new one later means passing underwriting first.

What is the 12-month trial right?

There is one real escape hatch, and it is narrow. If you joined a Medicare Advantage plan when you first became eligible for Medicare, and you disenroll within 12 months, you keep guaranteed issue rights to buy a Medigap policy. Pass the 12-month mark and that protection is gone.

Does Arizona protect you if you change your mind?

Arizona provides only the federal minimum Medigap protections. No birthday rule. No annual guaranteed issue period. Only four states, Connecticut, Massachusetts, Maine and New York, guarantee Medigap access to all beneficiaries year-round or annually. About a dozen more, including California, Oregon and Idaho, have narrower birthday or anniversary rules, and Minnesota added a limited annual guaranteed issue right for ages 65 to 70 effective August 1, 2026 (KFF). Arizona is on neither list.

In my practice, the people this hurts are rarely sick on the day they switch. They're healthy, the $0 premium looks like free money, and the diagnosis shows up in year three. That's when they call an insurer about a Medigap policy and find out what medical underwriting means.

What can you change, and when?

Six common moves, and only some of them come around twice. The fall window is broad. The winter window permits exactly one change, and only for people enrolled in a Medicare Advantage plan on January 1 (KFF). The last row of this table is the one worth reading twice, because it has no date on it at all.

What you want to do	Oct 15 to Dec 7	Jan 1 to Mar 31	When it takes effect
Join, drop or switch a Medicare Advantage plan	Yes	One change only, and only if you were in an MA plan on Jan 1	Jan 1 for fall changes; first of the month after the change in the winter window
Move from Original Medicare to Medicare Advantage	Yes	No. This window cannot be used to join MA for the first time	Jan 1
Move from Medicare Advantage back to Original Medicare	Yes	Yes, as your one allowed change	Jan 1, or first of the month after the change
Join, drop or switch a Part D drug plan	Yes	Only as part of your one MA change. Original Medicare enrollees cannot switch drug plans now	Jan 1, or first of the month after the change
Add Part D for the first time	Yes	No	Jan 1
Buy or switch a Medigap policy	No annual right. Medical underwriting applies in Arizona unless a federal guaranteed issue right applies.	No annual right. Medical underwriting applies in Arizona unless a federal guaranteed issue right applies.	Only if an insurer accepts your application

Read the bottom row again. Every other line has a date on it. Medigap doesn't. That asymmetry is why I ask patients to treat a move into Medicare Advantage as a decision with a long tail, not an annual experiment.

Why is the 2027 Part B premium not announced yet?

Because CMS does not release Part B figures until roughly mid-November, about a month into the enrollment window. As of this article's publication in early October 2026, the 2027 Part B standard premium, the Part B deductible and the IRMAA income brackets have not been published. That timing is normal every single year. It is not a delay, and it is not a reason to wait.

You don't need those numbers to choose. Everyone owes the Part B premium either way, so it is rarely the variable separating your options. The exception is a Medicare Advantage plan offering a Part B premium reduction, or giveback, which refunds part of it. What separates them is the network, the drug formulary, the cost sharing and the maximum out-of-pocket.

Plan-level details for 2027 are already in hand. Your plan mailed you an Annual Notice of Change by the end of September, listing next year's premium, copays and formulary changes. And if an agent quotes you a 2027 Part B figure before mid-November, they're guessing.

What is changing in Part D for 2027?

The standard Part D deductible rises to $700 for 2027, up from $615, and the annual out-of-pocket cap rises to $2,400, up from $2,100, per the CMS CY2027 Rate Announcement. Both are 2027 figures. Neither your monthly premiums nor any IRMAA surcharge counts toward that $2,400 cap.

Every Part D plan must also offer the Medicare Prescription Payment Plan, which spreads your out-of-pocket drug costs across the calendar year in monthly installments instead of charging them at the pharmacy counter (Arizona SHIP). You can opt in or out at any time. It doesn't lower your total cost. It smooths it, which matters when a $700 deductible would otherwise land entirely in January.

Ask about Extra Help, also called the Low Income Subsidy, if your income is at or near 150% of the federal poverty level. Social Security administers it, and it reduces or eliminates drug plan premiums, deductibles and copays. The 2027 limits aren't published yet, so apply rather than assume. I've had patients qualify who were certain they wouldn't.

How do Yavapai County's Medicare plans actually compare?

The spread between local plans is far wider than the marketing suggests. In 2026, Yavapai County had 20 general enrollment Medicare Advantage plans, 7 HMO and 13 PPO. Star ratings ranged from 2.5 to 4.0. No 5-star plan was offered in this county at all (Arizona SHIP).

The number I care most about is the maximum out-of-pocket. Across those 20 plans it ranged from $3,000 to $9,250. That's a $6,250 gap between two plans sold to the same person, in the same county, in the same year.

Premiums separate plans by a few hundred dollars a year. Maximum out-of-pocket separates them by thousands. In a quiet year the premium wins the comparison. In the year you have a hip replaced or a cancer diagnosis, the out-of-pocket maximum is the only number that matters. Shop as though you'll have a bad year. That's the year insurance exists for.

What about standalone Part D plans in Arizona?

Arizona had 10 standalone Part D plans in 2026. Premiums ran from $0.00 to $119.20 per month, deductibles from $0 to $615. Four plans carried a $0 premium alongside the full $615 deductible, while the $119.20 plan had no deductible at all (Arizona SHIP).

Coverage differed just as much. Formulary sizes ranged from 3,032 to 3,666 drugs. One plan's preferred pharmacy network was mail order only. Another listed no preferred pharmacies whatsoever. If you fill prescriptions at a specific pharmacy in Prescott or Prescott Valley, check that pharmacy by name before you enroll.

“The plan with the lowest premium might not have the lowest total cost for the drugs you are taking.”

Arizona SHIP

Why does almost nobody compare plans?

Mostly because comparing feels harder than it is. KFF found that 69% of Medicare beneficiaries did not compare their coverage against other options during Open Enrollment, 82% of Medicare Advantage drug plan enrollees did not compare their drug coverage, and only 42% visited Medicare.gov at all (KFF).

The follow-through numbers are just as small. Only 10% of Medicare Advantage drug plan enrollees and 21% of standalone drug plan enrollees actually switched (KFF). Meanwhile formularies, networks and copays change every January. Staying put is a legitimate choice. It should be a deliberate one.

How do you use Medicare Plan Finder in about 20 minutes?

1. Log in to your Medicare account instead of browsing as a guest. Logging in pre-populates your drug list from the last 12 months of your claims, which is faster and more accurate than typing from memory.
2. Confirm each dose and quantity. A 90-day supply and a 30-day supply price very differently.
3. Enter the pharmacy you actually use. If it's outside a plan's network, Plan Finder shows you the full uninsured price, which is exactly what you would pay.
4. Read the sort order carefully. Results rank by lowest estimated annual cost, meaning premium plus deductible plus drug costs, not by lowest premium.
5. Verify your doctors and hospital by calling their offices, not by trusting an online directory.

What are the rules on Medicare marketing calls and mail?

Federal rules ban most unsolicited contact. Under 42 CFR 423.2264, plans and their agents may not use door-to-door solicitation, approach you in common areas, send direct social media messages, or use telephone solicitation, robocalls, text messages or voicemail unless you asked for the contact first.

Unsolicited conventional mail and email are permitted. That's the entire explanation for your mailbox in October. It's legal. It's also written for a population, not for your prescriptions, your doctors or your health.

Before an in-person marketing appointment, an agent must obtain a written Scope of Appointment describing what will be discussed. If someone shows up at your door uninvited, calls you cold, or wants to pivot to a product you never agreed to discuss, that is your cue to end the conversation.

None of this is hypothetical. A 2022 Senate Finance Committee report found that beneficiary complaints about Medicare Advantage marketing more than doubled between 2020 and 2021, and documented agents telling seniors their doctors were in network when they were not. I've had patients arrive in January certain their specialist was covered because a salesperson said so.

Where can Prescott retirees get free, unbiased help?

Arizona's State Health Insurance Assistance Program offers free one-on-one Medicare counseling. It's federally funded, its counselors are not affiliated with the insurance industry, and they do not sell plans (Arizona DES). Statewide, call 1-800-432-4040. In Yavapai County, SHIP is run by the Northern Arizona Council of Governments: 928-251-0776.

Call early in the window rather than late. A counselor will sit down with your actual drug list and run the comparison alongside you, and unlike anyone who mailed you a brochure, they have nothing to sell. More detail is available at azship.org.

Bring these to the appointment:

• Your Medicare card and Medicare number
• Your current plan's Annual Notice of Change
• A written list of every prescription, with dose and quantity
• The name of the pharmacy you actually use
• The names of your doctors and your preferred hospital

Your Prescott Open Enrollment checklist

Ten steps, and most people finish them in one evening. Since only 42% of beneficiaries visit Medicare.gov during the window (KFF), simply opening Plan Finder puts you ahead of the majority. Work through this list between October 15 and Thanksgiving, while you still have room to fix a mistake.

1. Find your Annual Notice of Change and read the table of 2027 changes, not the cover letter.
2. Write down every prescription with its dose and quantity.
3. Log in at Medicare.gov and run Plan Finder with your real drugs and your real pharmacy.
4. Compare the maximum out-of-pocket, not just the premium. In Yavapai County that figure ranged from $3,000 to $9,250 in 2026.
5. Call your doctors' offices and your preferred hospital to confirm 2027 network status.
6. If you're considering leaving Original Medicare, ask whether you could pass medical underwriting five years from now. If the honest answer is no, treat the move as permanent.
7. If drug costs are the pressure point, ask about Extra Help and the Medicare Prescription Payment Plan.
8. Plan for the year you're likely to have, not the year you just had. Around here that includes summer, when heat risk climbs sharply after 65. An emergency visit in July is exactly what an out-of-pocket maximum exists for.
9. Book a free appointment with NACOG at 928-251-0776 if anything is unclear.
10. Make your change and save the confirmation number, in writing, before December 7.

What I tell my own patients

Do the comparison. Then decide slowly in one direction. Switching drug plans is a low-stakes annual chore: if next year's plan disappoints, you fix it next October. Leaving Original Medicare and a Medigap policy is a different category of decision, because Arizona law gives you no guaranteed way to reverse it.

None of this requires becoming an expert. It requires an hour, a list of your medications, and a conversation with someone who isn't paid on commission. If you're a patient here and you'd like to talk through how a coverage change might affect your care next year, get in touch before the window closes on December 7.

This article is general information, not individualized insurance or medical advice. Plan details change every year. Verify everything against Medicare.gov and your plan's own 2027 documents before you enroll.