2026 Medicare Open Enrollment Checklist: What Retirees Should Compare Before December 7

Medicare open enrollment is not just a plan-shopping chore. For retirees, the October 15 to December 7 window is a once-a-year chance to check whether next year’s doctors, prescriptions, premiums, deductibles, networks, and out-of-pocket risks still fit the household retirement plan. A plan that looked cheap last year can become expensive if one medication moves tiers, a specialist leaves network, or income pushes the retiree into higher Medicare surcharges.

Why the 2026 Review Matters

Open enrollment happens every fall, but the 2026 review deserves extra attention because healthcare costs are already one of the least forgiving retirement assumptions. Recent retiree healthcare estimates continue to put lifetime medical costs in six-figure territory for a single 65-year-old, and those estimates often do not include every possible care shock. Meanwhile, Medicare Advantage networks, Part D formularies, drug tiers, preferred pharmacies, and plan premiums can change from one year to the next.

That means the right question is not “Do I like my current plan?” The better question is: “If I had to choose today based on my 2027 doctors, prescriptions, income, and retirement budget, would I choose this plan again?” If the answer is not clearly yes, open enrollment is the time to compare.

The Seven-Point Medicare Open Enrollment Checklist

Use this checklist before December 7. Married couples should run it separately for each spouse because drug lists, doctors, and risk tolerance can be very different.

Coverage, prescriptions, and total annual risk

1. Confirm every doctor and hospital. Check primary care, specialists, preferred hospitals, pharmacies, and any recurring therapy or treatment locations.
2. Enter every prescription exactly. Include dosage, frequency, brand versus generic, pharmacy preference, and whether you use 30-day or 90-day fills.
3. Compare total annual cost. Add premiums, deductibles, expected copays, coinsurance, drug costs, and realistic out-of-pocket exposure.
4. Check restrictions. Prior authorization, step therapy, referral rules, and quantity limits can matter as much as the monthly premium.
5. Review travel and relocation plans. Snowbirds, frequent travelers, and retirees considering a move should be cautious with narrow networks.
6. Estimate Medicare surcharges. Higher income can affect Part B and Part D through IRMAA, so income planning belongs in the Medicare review.
7. Stress-test one bad health year. Compare what happens if you need surgery, a new specialist, or an expensive medication next year.

Part D: The Medication Math Can Change Fast

Prescription coverage is one of the easiest places to make a costly mistake. A plan can keep the same name while changing premiums, formularies, pharmacy networks, deductibles, copays, or prior authorization rules. Retirees taking brand-name drugs should be especially careful because one tier change can outweigh a year of premium savings.

For example, assume Robert pays $12 per month for a Part D plan and takes four medications. Three are low-cost generics. The fourth is a brand-name heart medication. If the plan’s premium rises only $5 per month, the headline increase is $60 per year. But if the heart medication moves to a less favorable tier and costs $95 more per month, Robert’s real increase is $1,200 per year. A competing plan with a $38 monthly premium could still be cheaper overall.

This is why retirees should calculate the full-year drug cost. For a deeper drug-specific review, pair this checklist with Bullseye’s guide to 2026 Medicare Part D changes.

Medicare Advantage: Look Beyond the Extras

Network and prior authorization risk

Medicare Advantage plans can be attractive because they may bundle drug coverage and extras such as dental, vision, hearing, transportation, or wellness benefits. But retirees should weigh those extras against provider access, referral rules, prior authorization, network limits, and the plan’s maximum out-of-pocket exposure.

Suppose Linda is choosing between a $0 premium Medicare Advantage HMO with an $8,500 maximum out-of-pocket limit and a higher-premium alternative that keeps her cardiologist, nearby hospital, and preferred pharmacy in network. If she is healthy and rarely travels, the first plan might work. If she has a chronic condition, sees specialists, or spends months in another state, the lower premium may be a poor trade.

If you already regret a plan choice, review the rules in Bullseye’s Medicare Advantage switching guide. The fall Annual Enrollment Period and the separate Medicare Advantage Open Enrollment Period are different windows with different choices.

Original Medicare, Medigap, and Predictable Cash Flow

Premium certainty versus variable costs

Original Medicare plus Medigap and Part D often has higher monthly premiums than a low-premium Medicare Advantage plan. The trade-off is broader provider access and more predictable out-of-pocket exposure, depending on the Medigap policy. For retirees who value nationwide provider flexibility or who have significant health needs, that predictability can be worth modeling.

The planning issue is cash flow. A Medigap premium of $175 per month is $2,100 per year before Part D, dental, vision, or drug costs. A Medicare Advantage plan may have a lower premium but greater variable costs. Neither structure is universally better. The question is which structure your retirement budget can absorb in both normal and bad health years.

Do Not Forget IRMAA and Income Timing

Medicare premiums are not isolated from tax planning. Income-related monthly adjustment amounts can apply to Part B and Part D based on modified adjusted gross income from two years earlier. A Roth conversion, large IRA withdrawal, capital gain, home sale, or inherited IRA distribution can raise Medicare costs later.

If you are close to an IRMAA threshold, the open-enrollment review should include a tax-calendar review. A plan that is affordable at the standard Part B premium may feel different if both spouses pay surcharges. Use Bullseye’s IRMAA income guide to understand what counts before making a large year-end income move.

Using Bullseye for Medicare Open Enrollment

Bullseye cannot choose a Medicare plan for you, determine legal eligibility, or replace Medicare.gov, SHIP counseling, or a licensed insurance professional. What it can do is help you model the retirement cash-flow impact after you identify realistic plan options and costs.

Create one scenario with your current plan’s premiums, expected drug costs, and out-of-pocket estimate. Create a second scenario with a higher-premium but lower-risk option such as Original Medicare plus Medigap and Part D. If you are married, model each spouse’s costs separately when they differ. Then compare taxes, withdrawals, Medicare costs, and asset balances year by year through age 95.

This pairs well with Bullseye’s broader 2026 retiree healthcare cost estimate and the IRMAA calculator. The goal is not to predict every medical bill. The goal is to keep Medicare decisions from quietly undermining the rest of the retirement plan.

Bottom Line

The 2026 Medicare open enrollment review should be a structured planning exercise, not a quick glance at next year’s premium. Verify doctors, price prescriptions, compare total annual cost, review network and travel needs, and model the result inside the retirement budget. If the plan only looks good in a perfect health year, keep comparing before December 7.