Medicare’s annual open enrollment runs October 15 through December 7, 2026, and the decisions you make then take effect January 1, 2027. The six weeks before it opens are the best time to gather your documents, read the plan-change notice that arrives by September 30, and decide whether your current coverage still fits, so you are comparing plans rather than scrambling when the window opens.
🔍 When is my Medicare enrollment window?
Enter the month you turn (or turned) 65 to see your personal 7-month Initial Enrollment Period and how the Oct 15 – Dec 7 window applies to you.
Month and year of your 65th birthday:
General information, not enrollment advice; confirm at Medicare.gov or 1-800-MEDICARE.
Key Takeaways
Enrollment window: October 15 to December 7; changes start January 1, 2027
Watch the mail: your Annual Notice of Change (ANOC) must arrive by September 30 and lists every 2027 change to your plan
You can switch Medicare Advantage plans, move between Original Medicare and Advantage, or change Part D drug plans
Free, unbiased help is available through your State Health Insurance Assistance Program (SHIP)
Doing nothing keeps your current plan, including any premium, copay, or network changes it has made
What you can change during open enrollment
Change
Allowed Oct 15 – Dec 7?
Switch from one Medicare Advantage plan to another
Yes
Leave Medicare Advantage for Original Medicare (plus a Part D plan)
Yes
Join Medicare Advantage from Original Medicare
Yes
Change or drop a Part D prescription drug plan
Yes
Buy or switch a Medigap (supplement) policy
Not guaranteed; medical underwriting may apply outside protected windows
Medigap is the piece most people misunderstand. Open enrollment does not give you a guaranteed right to buy a supplement policy; that right generally exists only in the six months after you first enroll in Part B and in a handful of special situations. If your plan is to leave Medicare Advantage for Original Medicare with a Medigap policy, confirm in September that an insurer will accept you before you make the switch.
The six-week checklist
Week 1 (late August): gather your records
List every prescription with dosage and how often you fill it. This list drives the Part D comparison and is the single biggest source of savings.
List your doctors, hospitals, and pharmacies, including any specialist you expect to need next year.
Pull this year’s costs. Add up premiums, deductibles, copays, and drug costs from January through August to get a real baseline.
Create or log in to your Medicare.gov account. The Plan Finder can save your drug list and pharmacies so the comparison takes minutes instead of hours.
Week 2 (early September): understand your current plan’s 2027 changes
Watch for the ANOC. Every Medicare Advantage and Part D plan must mail it by September 30. It shows next year’s premium, deductible, copays, drug tier changes, and provider network changes side by side with this year’s.
Check the drug formulary specifically. A drug moving from tier 2 to tier 4, or being dropped entirely, can cost far more than a premium increase.
Confirm your doctors are still in network for 2027, not just 2026. Networks change every year.
Week 3 (mid-September): decide whether you need to shop
If your ANOC shows no meaningful changes, your doctors are still covered, your drugs are still on the formulary at the same tier, and your total cost this year was manageable, staying put is a legitimate choice. If any of those changed, or your health needs changed, plan to compare. People who compare Part D plans each year often find a cheaper option because drug pricing between plans shifts significantly from year to year.
Week 4 (late September): line up help
Book a SHIP appointment. State Health Insurance Assistance Programs offer free, one-on-one counseling from trained volunteers who do not sell insurance. Slots fill quickly in October, so booking in September matters.
Note the 2027 Part B premium and deductible when the government announces them, typically in the fall. They are deducted from Social Security checks and affect your net benefit.
Understand the Part D out-of-pocket cap. Since 2025 there has been an annual cap on what you pay for covered drugs, adjusted each year; the 2027 figure will appear in plan materials. Plans also offer a payment option that spreads costs across the year.
Week 5 (early October): preview plans
Plan details for the coming year are posted on Medicare.gov on October 1, two weeks before enrollment opens. Use that window to run the Plan Finder with your saved drug and pharmacy list, sort by estimated total annual cost rather than premium alone, and read the star ratings. A plan with a $0 premium and a restrictive network or high drug costs can be far more expensive than one with a modest premium.
Week 6 (mid-October): enroll
Once you have chosen, enroll online through Medicare.gov, by calling 1-800-MEDICARE, or directly with the plan. Enrolling in a new plan automatically disenrolls you from the old one, so do not cancel anything separately. Keep the confirmation number. If you change your mind, you can enroll again before December 7; the last enrollment received is the one that takes effect.
Common mistakes to avoid
Comparing on premium only. Total annual cost, including drugs and expected visits, is the number that matters.
Assuming your plan did not change. Even the same plan name can carry new copays and a smaller network in 2027.
Ignoring the mail. The ANOC is easy to mistake for marketing and discard.
Responding to sales calls. Medicare will not call you to sell a plan; unsolicited calls are a common source of enrollment errors and scams.
Missing the Medigap underwriting issue when leaving Medicare Advantage.
If you miss the window
Medicare Advantage members get a second chance from January 1 to March 31, when they can switch to another Advantage plan or return to Original Medicare with a Part D plan, but cannot move from Original Medicare into Advantage. Special enrollment periods also exist for moves, loss of other coverage, and plan terminations. Outside those, you are generally locked in until the next October.
FAQ
Does open enrollment apply if I have Original Medicare and no drug plan?
Yes. You can add a Part D plan during the window, though a late enrollment penalty may apply if you went without creditable drug coverage for more than 63 days after becoming eligible.
Is this the same as ACA marketplace open enrollment?
No. The ACA marketplace window opens November 1 and covers people under 65 without Medicare. The dates overlap, which causes confusion, but the programs are separate.
Can I keep my Medigap policy if I switch Part D plans?
Yes. Medigap and Part D are separate; changing a drug plan does not affect a supplement policy.
When will 2027 premiums be published?
Plan-level premiums appear on Medicare.gov on October 1. The standard Part B premium and deductible are announced by the federal government in the fall, usually before enrollment opens or shortly after.
A one-page summary to print
Late August: drug list, provider list, this year’s costs, Medicare.gov account. September: read the ANOC, check the formulary and network, book SHIP. October 1: preview 2027 plans and sort by total cost. October 15 to December 7: enroll and keep the confirmation. January 1: new coverage begins, so refill prescriptions and confirm appointments under the new plan in the first week.
Sources
Medicare.gov, Joining a health or drug plan and enrollment periods
Centers for Medicare & Medicaid Services, Annual Notice of Change requirements
State Health Insurance Assistance Program (shiphelp.org)
This is general information, not personalized insurance advice. Last updated August 26, 2026 · InfoBrief Staff
Quick answer: Request an itemized bill before paying anything, compare it against the Explanation of Benefits from your insurer, and dispute in writing with the billing department. Do not pay while a claim is still processing, and do not assume the first number is final. Studies of hospital billing have repeatedly found error rates high enough that reviewing the itemized list is worth the time on any bill of consequence.
Key Takeaways
The Explanation of Benefits is not a bill; never pay a provider bill that arrives before the EOB
Always request the itemized bill with billing codes, not the summary
Look for duplicates, services not received, quantity errors, upcoding, and unbundling
The No Surprises Act covers emergency care and out-of-network providers at in-network facilities
Even correct bills are negotiable: ask for self-pay rates, financial assistance, and interest-free plans
The two documents, and why they are not the same thing
Confusing these is the most common reason people pay bills they do not owe.
The Explanation of Benefits comes from your insurer. It is not a bill. It shows what the provider charged, what the insurer’s negotiated rate was, what the insurer paid, and what portion is your responsibility. It usually carries the line “This is not a bill” in small type that everyone skips.
The bill comes from the provider and should match the patient responsibility figure on the EOB. When it does not match, something is wrong, and it is often that the provider billed you before the insurer finished processing, or billed you the full charge rather than the negotiated rate.
The rule that follows: never pay a medical bill that arrives before the corresponding EOB.
Ask for the itemized bill, not the summary
What arrives in the mail is usually a summary showing a department and a total. An itemized bill lists every charge with its billing code. You are entitled to request it, and providers must supply it.
What to look for once you have it:
Duplicate charges for the same service on the same day
Services you did not receive, including tests that were ordered then cancelled
Quantity errors, such as being billed for a full box of supplies rather than one item
Upcoding, where a routine visit is billed at a more complex and expensive level
Unbundling, where procedures that should be billed together at one rate appear as separate line items
Room charges for days you were not admitted, including the discharge day
You do not need to be a coder to catch most of these. Duplicates, wrong dates, and services you know did not happen account for a large share of errors.
Federal protections worth naming in your dispute
Two rules give you leverage, and citing them by name changes how billing departments respond.
The No Surprises Act protects you from balance billing for emergency care and for out-of-network providers treating you at an in-network facility, such as an anesthesiologist or pathologist you never chose. In those cases you owe only in-network cost sharing.
The good faith estimate requirement applies if you are uninsured or paying cash. Providers must give you a written estimate in advance, and if the final bill exceeds it by $400 or more, you can dispute through a federal patient-provider dispute resolution process.
Separately, medical debt has been treated differently by the major credit bureaus in recent years, with paid medical collections removed and a waiting period before unpaid medical collections appear. Rules in this area have been in flux, so verify current status rather than assuming either the old or new treatment applies.
How to actually run the dispute
Call the insurer first if the EOB looks wrong. Ask why a claim was denied or processed at out-of-network rates. Many denials are coding errors the provider can resubmit.
Call the provider’s billing department with the itemized bill in front of you and a specific list of line items you are questioning.
Put it in writing. Send a letter or portal message stating the account number, the specific charges disputed, and what you are asking for. Keep a copy.
Appeal formally if the insurer denies. Every plan has an internal appeal process, and if that fails, an external review by an independent third party.
Escalate to your state insurance department or attorney general if the provider or insurer stops responding.
Throughout, keep a log with dates, names, and reference numbers. Billing disputes are resolved by whoever can document what was said.
Reducing what you owe on a correct bill
Even accurate bills are often negotiable, because providers prefer partial payment over collections.
Ask for the self-pay or prompt-pay rate, which is frequently well below the billed charge. Ask about financial assistance, which nonprofit hospitals are required to offer and which often extends further up the income scale than people expect. Request an interest-free payment plan, which most hospitals provide. And if you are near the threshold for charity care, ask what documentation would qualify you.
What to avoid: putting a large medical bill on a credit card or a medical credit card with deferred interest. That converts a debt that is often negotiable and interest-free into one that is neither.
FAQ
Should I pay the bill while disputing it? Not the disputed portion. Pay any part you agree you owe and tell the provider in writing that the rest is under dispute.
How long do I have to dispute? There is no single deadline, but insurer appeal windows are limited, often 180 days from the denial. Act promptly.
Can a hospital refuse to give me an itemized bill? No. Request it in writing if the first call does not produce one.
What if it already went to collections? You can still dispute. Send a written dispute to the collector within 30 days of first contact to require validation of the debt.
Is it worth reviewing a small bill? The same errors occur at every size, but the effort is best spent on bills large enough to matter to you.
Last updated: August 19, 2026. Written by the InfoBrief Editorial team. Rules and prices change; confirm with the official source before acting. See our disclosure.
Quick answer: The deductible is what you pay before the plan starts sharing costs. A copay is a flat fee per visit. Coinsurance is your percentage after the deductible. The out-of-pocket maximum is the ceiling on what you can lose in a year, and it is the single most important number on the page. Premiums are what you pay to have the plan at all, and they do not count toward any of those limits.
Key Takeaways
Premiums never count toward your deductible or out-of-pocket maximum
The out-of-pocket maximum is your worst-case ceiling and the most important number to compare
Compare total annual exposure: 12 months of premium plus the out-of-pocket maximum
All these limits apply to in-network care; out-of-network often has separate and higher limits
The No Surprises Act protects you in emergencies and for out-of-network providers at in-network facilities
Health Plan Comparison Tool
Enter two plans and an estimate of your yearly medical costs. This shows what each plan actually costs you in a light year, a heavy year, and the worst case.
Plan A
Plan B
This is an estimate for in-network care. It assumes costs apply to the deductible, then coinsurance, capped at the out-of-pocket maximum. Copays, services covered before the deductible, and separate prescription tiers are not modeled. Check the Summary of Benefits and Coverage for each plan.
The four numbers, in the order money actually moves
Plan documents list these terms alphabetically, which is why they confuse people. Here is the order you actually encounter them.
Premium. A monthly charge for having coverage. You pay it whether or not you see a doctor, and it does not count toward the deductible or the out-of-pocket maximum. It is the only one of these numbers you are guaranteed to pay in full.
Deductible. The amount you pay yourself before the plan begins paying its share. On a $2,000 deductible, the first $2,000 of covered care is yours. Important exception: most plans cover preventive care and some services at a copay before the deductible is met, so read what is exempt.
Copay. A fixed dollar amount for a specific service, such as $30 for a primary care visit. Predictable, and often applies from day one.
Coinsurance. After the deductible, you pay a percentage rather than a flat fee. A plan with 20% coinsurance means a $5,000 procedure costs you $1,000. This is where large bills come from.
Out-of-pocket maximum. Once your deductible, copays, and coinsurance add up to this number, the plan pays 100% of covered in-network care for the rest of the year. Premiums do not count toward it.
Why the out-of-pocket maximum matters more than the premium
Most people compare plans by premium because it is the number in the biggest font. That answers the wrong question. The premium tells you your cost in a healthy year. The out-of-pocket maximum tells you your cost in a bad one.
The real comparison is total annual exposure: twelve months of premium plus the out-of-pocket maximum. A plan with a $200 monthly premium and a $9,000 maximum exposes you to $11,400. A plan at $380 per month with a $4,000 maximum exposes you to $8,560. The second plan costs more every month and less when something goes wrong.
Which to choose depends on whether you could absorb the worst case. If a $9,000 bill would be catastrophic for your finances, the cheaper premium is not actually cheaper.
The distinction that causes the largest surprise bills
Every number above applies to in-network care. Out-of-network care often has a separate deductible, a separate and much higher out-of-pocket maximum, or no maximum at all.
The federal No Surprises Act protects you in situations where you had no realistic choice: emergency care, and out-of-network providers working at an in-network facility, such as an anesthesiologist or radiologist you never selected. In those cases you pay in-network rates.
It does not protect you when you choose an out-of-network provider knowingly. That is why verifying network status matters before a scheduled procedure, and why “my hospital is in network” is not the same as “everyone treating me at that hospital is in network.”
What to check before choosing, in fifteen minutes
Your doctors. Search each one in the plan’s provider directory, and call the office to confirm, since directories are frequently out of date.
Your prescriptions. Look up each drug in the plan’s formulary and note its tier. A drug moving from tier 2 to tier 4 can cost hundreds more per month.
Whether a referral is required. HMO plans generally require one to see a specialist; PPO plans generally do not.
The family deductible structure. Some plans require the entire family deductible to be met before anyone gets coverage; others let each member’s individual deductible apply.
What is exempt from the deductible. Plans that cover primary care and generics at a copay before the deductible behave very differently from plans that do not.
High-deductible plans and the HSA angle
A high-deductible health plan trades a lower premium for a larger deductible, and qualifies you to contribute to a Health Savings Account. The HSA is the only account in the tax code that is untaxed going in, growing, and coming out for medical expenses.
The arithmetic that decides it: if the annual premium savings plus any employer HSA contribution exceeds the increase in your worst-case exposure, the high-deductible plan wins even in a bad year. If it does not, you are paying for a tax benefit you may not use. Our guide to how an HSA works and who qualifies covers the contribution rules and the Medicare timing trap.
FAQ
Does my premium count toward the deductible? No. Premiums are separate from every other number and never count toward the deductible or out-of-pocket maximum.
What resets each year? Deductibles and out-of-pocket maximums reset on the plan year, which is usually January 1 but may differ for employer plans.
Is a lower deductible always better? No. It usually comes with a higher premium. Compare total annual exposure rather than any single number.
What if I get a surprise bill anyway? Ask the provider for an itemized bill, compare it to your explanation of benefits, and dispute errors. If it involves emergency care or an out-of-network provider at an in-network facility, cite the No Surprises Act.
Where can I get free help comparing plans? HealthCare.gov has assisters and navigators at no cost, and employers usually offer a benefits counseling line during open enrollment.
Last updated: August 19, 2026. Written by the InfoBrief Editorial team. Rules and prices change; confirm with the official source before acting. See our disclosure.
