Medicare Open Enrollment Guide: What You Can Change and When

Medicare open enrollment is your annual opportunity to review and change your Medicare coverage for the coming year. Making the right choices during this window can save you money and ensure you have the coverage that fits your health needs. This guide provides the exact 2026 deadlines for 2027 coverage and a clear checklist so you can enroll or switch plans with confidence. 2026 Medicare open enrollment deadlines Initial Medicare Open Enrollment Period: October 15, 2026 through December 7, 2026. Any changes you make will take effect on January 1, 2027. If you are already enrolled in a Medicare Advantage plan, you have an additional Open Enrollment Period from January 1 to March 31, 2027 to switch plans or return to Original Medicare. These dates are firm. Missing the December 7, 2026 deadline means your current coverage will automatically renew for 2027 with whatever rates and benefits the plan sets. Step-by-step checklist for Medicare open enrollment Review your current plan Log into Medicare.gov or check your Annual Notice of Change letter that arrives in September or October. Note any changes in premiums, deductibles, drug coverage, or network for 2027 . List your doctors, hospitals, and prescriptions Make sure your current or new plan includes your preferred providers in-network and that all your medications are on the formulary at an affordable tier. Compare your options Original Medicare (Parts A and B) plus a Medigap supplement and standalone Part D drug plan Medicare Advantage (Part C) plans that bundle A, B, and usually D Key factors to compare: monthly premium, deductible, out-of-pocket maximum, extra benefits (dental, vision, hearing, gym membership), and star ratings. Check for Extra Help or low-income subsidies If your income qualifies, you may receive help paying for Part D premiums and drugs. Apply or reapply during open enrollment. Enroll or make changes Use Medicare.gov, call 1-800-MEDICARE, or work with a licensed agent. Keep confirmation numbers and plan details. Verify after enrollment You will receive new cards in the mail. Confirm your doctors and prescriptions are still covered once the new year begins. Common mistakes to avoid Assuming your current plan is automatically the best for next year. Focusing only on the lowest premium without checking the drug formulary or network. Forgetting that Medicare Advantage plans have networks and prior authorization rules that Original Medicare does not. Next steps with Bill Advantage Use Bill Advantage’s Health Insurance Plan Comparison tool (available in the Member tier and above) to model Original Medicare versus Medicare Advantage options side by side with your specific doctors and prescriptions. Pair it with the Medicare Navigator for plain-English explanations of Part D and Medigap choices.

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Bill Advantage is a document literacy tool. Nothing in this article constitutes legal or medical advice.