Medicare Open Enrollment runs from October 15 through December 7, 2026. Whatever you choose takes effect January 1, 2027.
You may not need to change anything. If your plan still covers your doctors and your drugs, staying put is a fine choice, and you do not have to sign up again to keep it. But a short check is worth it this year. Arizona has more plans than last year, fewer of them are open to most people than the headline number suggests, and two drug cost limits went up.
Arizona has 148 plans for 2027, but only 90 are open to anyone
Arizona went from 133 Medicare Advantage plans to 148. Of those, 58 are Special Needs Plans with eligibility rules. That leaves 90 that anyone can join.
If you read that Arizona has 148 plans and then search your own ZIP code, the list you can join can be much shorter. That is not an error.
Special Needs Plans are only for people who also have Medicaid, have certain serious chronic conditions, or need the level of care a nursing home gives. If none of that applies to you, you choose from the other 90. Plans are also sold county by county, so the count for your county can be far lower again.
Medicare Advantage plans in five Arizona counties, 2027
| County | All plans | Open to anyone |
|---|---|---|
| Maricopa | 92 | 52 |
| Pima | 88 | 52 |
| Pinal | 71 | 47 |
| Yavapai | 31 | 20 |
| Apache | 12 | 7 |
Scroll the table sideways to see every column.
Counted from the CMS 2027 Landscape file. The gap between the two columns is Special Needs Plans. Statewide, Arizona has 148 plans, and 90 are open to anyone.
The spread is wide. Maricopa County and Pima County each have 52 plans open to anyone. Yavapai has 20. Apache has 7.
A long list is not the same as a good fit. The real work is cutting your county's list down to the plans that cover the doctors you see and the drugs you take. That often leaves only a few worth comparing.
Two drug cost limits went up for 2027
The Part D out-of-pocket cap rose from $2,100 to $2,400. If you reach the cap in both years, you pay $300 more.
The average premium in Arizona went down. CMS says the average Medicare Advantage premium in the state fell from $4.47 a month in 2026 to $2.81 in 2027. Nationally, CMS projects the average to fall from $14.37 to $12.00.
But the premium is only one part of what you pay. CMS also sets two limits for Medicare's standard drug benefit, and both went up.
Medicare's standard Part D benefit, set by CMS
| What it is | 2026 | 2027 |
|---|---|---|
| Highest deductible Medicare allows | $615 | $700 |
| Out-of-pocket cap, after which you pay $0 for covered drugs | $2,100 | $2,400 |
Scroll the table sideways to see every column.
These are program-wide limits that CMS sets each year, not what any one plan charges. Many plans have a lower deductible or none at all. The cap includes any deductible you pay. Your Annual Notice of Change shows your own plan's numbers.
The cap is the number to watch. Once your out-of-pocket costs for covered drugs reach it, you pay nothing more for covered Part D drugs for the rest of the year. If you hit $2,100 in 2026 and hit $2,400 in 2027, that is $300 more out of your pocket.
If your drug costs are modest, this change may not touch you. If you take a costly specialty drug, it may matter more than any premium.
Drug plans in Arizona: most enrollees cannot find a lower premium
Arizona has 9 standalone drug plans for 2027. CMS says 38.67% of people in one can find a lower premium than they paid in 2026.
CMS ran a temporary program for standalone drug plans called the Part D Premium Stabilization Demonstration. It ends after 2026. Nationally, CMS projects the average standalone drug plan premium to go from $35.09 to about $36 a month. That sounds small, but an average hides what happens to your plan.
Standalone Part D drug plans in Arizona, 2027
| What CMS reports | Arizona |
|---|---|
| Standalone drug plans available | 9 |
| Share of enrollees who can find a lower premium than in 2026 | 38.67% |
| Share of enrollees who get Extra Help | 22.48% |
Scroll the table sideways to see every column.
From the CMS 2027 fact sheet for Arizona. Shares are of people already in a standalone drug plan. CMS measures access to a lower premium, not a lower total cost.
About four in ten Arizonans in a standalone drug plan can find a lower premium than this year. About six in ten cannot. For most people here, the bigger savings may come from how a plan covers their drugs, not from its monthly price.
That is why the drug list comes first. Check that each of your drugs is covered, which tier it is on, and whether the plan needs to approve it before it pays.
Open Enrollment is not the window for a Medicare Supplement
October 15 to December 7 is for Medicare Advantage and Part D. Medigap runs on its own rules, and Arizona has no birthday rule.
Mixing these up can be costly.
What you can do between October 15 and December 7: join, switch, or drop a Medicare Advantage plan, and join, switch, or drop a Part D drug plan. You can also move between Original Medicare and Medicare Advantage.
What this window does not do: give you a right to buy a Medicare Supplement, also called Medigap. Your one-time Medigap Open Enrollment Period is the six months that start when you are 65 or older and enrolled in Part B. Federal law also gives you guaranteed-issue rights in a short list of cases. Two examples: your Medicare Advantage plan stops serving your area, or you joined a Medicare Advantage plan when you first got Medicare at 65 and left it within the first year.
Outside those cases, an Arizona insurer can ask health questions and turn you down.
What to do between now and December 7
Four checks, in this order. The first one is already in your mailbox.
If all four come back clean, you may not need to do anything.
- Read your Annual Notice of Change. Your plan had to send it so it reached you by September 30. It lists what changes for 2027: premium, copays, deductible, and drug list. If you did not get one, call your plan.
- Check that your drugs are still covered the same way. Drug lists change each year. A drug can move to a higher tier and cost you more, even if your premium went down.
- Check that your doctors are still in network. Medicare Advantage networks are local, and they change. People often find out in January, when it is harder to fix.
- Compare total cost among the plans sold in your county. Add the premium, the deductible, and what your drugs cost on each plan. A $0 premium plan is not free if it puts your drug on a higher tier.