Your 2027 Guide to Medicare Part D in Missouri

Drug coverage under Medicare got a major overhaul for 2027. This guide covers the $2,400 out-of-pocket cap, how the coverage phases work, and what people in Missouri should know — no jargon, no sales pitch.

Sorting out Medicare in Missouri? The first thing worth knowing is that plan availability is set at the county level, not statewide — two people an hour apart can have genuinely different options. That's why this guide is organized city by city.

Statewide, about 55% of Missouri Medicare members are in a Medicare Advantage plan rather than Original Medicare — an official figure that varies widely county to county.

On this page: the companies active in Missouri, a plain-language explanation of how Medicare fits together, 2027 costs, enrollment timing, free help, and links to every Missouri city guide. We don't rank or recommend plans.

How Part D drug coverage works

Medicare Part D covers prescription drugs. You can get it two ways: as a stand-alone plan added to Original Medicare, or built into a Medicare Advantage plan that includes drug coverage. Either way, the basic structure is set by Medicare and the plans are run by private insurers.

For 2027, coverage moves through three phases — a deductible phase (no more than $700), an initial coverage phase, then a catastrophic phase. The old 'donut hole' gap is gone, and an annual out-of-pocket cap limits what you pay for covered drugs. An optional Medicare Prescription Payment Plan also lets you spread those costs across the year.

This guide explains those rules as they apply in Missouri. Specific drug lists and pricing vary by plan, so for plan-by-plan detail we point you to Medicare's Plan Finder rather than ranking plans ourselves.

What Medicare costs in 2027

It helps to separate the costs everyone shares from the costs that vary by plan. The program-level numbers here are set nationally — the same whether you're in a big city or a rural county.

Part B premium. Most people pay the standard Part B premium of $202.90 a month in 2026 (2026 amount; 2027 figure will be posted when CMS releases it). Part A is premium-free for most people who worked and paid Medicare taxes long enough.

Part D drug costs. In 2027, a Part D plan's yearly deductible can be no more than $700, and a $2,400 cap limits what you pay out of pocket for covered prescriptions across the year — a real change for anyone with high drug costs.

Higher earners pay more for Parts B and D through an income-related adjustment called IRMAA, which for 2026 starts above $109,000 in annual income for an individual and is based on your 2024 tax return. Most people fall below that line and pay the standard amounts. The 2027 brackets will be posted when CMS releases them.

Plan-specific costs. What an individual plan charges — its premium, deductible, copays, and what it covers — varies by plan and changes yearly. We don't publish those figures or rank plans; Medicare's Plan Finder shows the current details for your situation, and a licensed agent can walk you through them.

Your Medicare enrollment calendar

The dates that follow are set federally, so they don't change from state to state — only your personal timing does.

It starts with your Initial Enrollment Period — the 7-month window around your 65th birthday month — the window around turning 65 when you first sign up. Missing it can mean late penalties that stick around, so it's the one not to sleep on.

After that, the big recurring window is the Annual Enrollment Period, October 15 – December 7, when anyone can join, switch, or drop an Advantage or Part D plan for a January 1 start. And if you're already in an Advantage plan, the Medicare Advantage Open Enrollment (January 1 – March 31) gives you one more chance to change course.

Life events — a move, a loss of other coverage — can also trigger a Special Enrollment Period. The calendar below shows the whole year at a glance.

Getting unbiased help in Missouri

You never have to make these decisions alone, and you don't have to pay for good help. A few free, trustworthy starting points:

Medicare.gov and 1-800-MEDICARE (TTY 1-877-486-2048) are the official sources for plan details and the Plan Finder. Licensed agents can also compare options with you and handle enrollment.

And to be clear about who we are: MyMedicarePlans.org is a privately owned, independent educational resource. We are not Medicare, not a government agency, and not affiliated with one. We publish plain-language information to help you get oriented — then point you to the official sources and licensed professionals for decisions about specific plans.

Missouri cities

Pick your city for the county-level picture, the companies active in your area, and local guides: