- Compare total yearly cost — premium plus copays — not just the monthly premium, and check every drug against the plan's formulary.
- Confirm the pharmacy is preferred, not just in-network, and check tier placement and prior authorization rules for each medicine.
- A parent's plan choice is theirs to make; a caregiver's job is to gather the facts, present the comparison, and handle the paperwork once they decide.
- Annual Enrollment Period (Oct 15 – Dec 7) is the yearly window to switch plans, and the 2026 out-of-pocket cap of $2,100 limits covered drug costs.
If your parent asks you to help them pick a Medicare Part D plan, the wrong choice can mean a drug that is not covered, a pharmacy that charges more, or surprise costs in January. This checklist walks you through the comparison, step by step.
Start with the medicine list, not the premium
The most common mistake is shopping by monthly premium. A low-premium plan can be the most expensive plan of all if your parent's drugs sit on high tiers or are not covered at all.
Build a complete list first:
- Every prescription drug, with the exact name, dose, and how often it is taken
- Whether a generic version is used or a brand-name drug is required
- The pharmacy your parent prefers, including whether mail order is an option
With that list in hand, you can compare plans on what actually matters: what each plan charges for those specific drugs.
Compare total yearly cost on Medicare.gov Plan Finder
Medicare.gov Plan Finder is the free official comparison tool, and it does the math for you. Enter your parent's drugs, doses, and preferred pharmacy, and it estimates total yearly cost for each available plan — premium plus copays and coinsurance combined. That total is the number to compare, not the premium alone.
When you review the results, check four things for each plan:
- Formulary coverage. Is every drug on the plan's list of covered drugs? A drug that is not covered means paying full price or filing an exception request.
- Tier placement. Drugs are grouped into tiers, and higher tiers mean higher copays. A drug that moved to a higher tier is the most common cause of a January surprise.
- Utilization rules. Check whether any drug requires prior authorization or step therapy — rules that can delay a fill until extra paperwork is approved.
- Pharmacy status. Confirm the pharmacy is preferred, not just in-network. Preferred pharmacies charge lower copays, and the difference adds up over a year of refills.
Run this comparison every year. Plans change their formularies, preferred pharmacies, and cost-sharing annually, so last year's cheapest plan may not be the cheapest next year.
Understand the 2026 costs before you compare
Knowing the year's cost structure helps you read the comparison results. In 2026, no Part D plan can charge a standard deductible higher than $615, and many plans charge less or waive it for certain drug tiers. After the deductible, your parent generally pays 25% of the cost of covered drugs until out-of-pocket spending reaches $2,100. Once that $2,100 cap is reached, covered drugs cost $0 for the rest of the year. The old coverage gap, sometimes called the donut hole, was eliminated in 2025.
Two more cost protections are worth knowing about:
- Insulin is capped at $35 for a 30-day supply of covered insulin, and the deductible does not apply to it — but confirm the plan covers your parent's specific insulin product.
- CDC-recommended adult vaccines cost $0 under Part D, including the shingles vaccine, so a plan choice never has to turn on vaccine cost.
If costs are still unaffordable, ask about Extra Help through Social Security or a State Pharmaceutical Assistance Program — many eligible beneficiaries never apply.
Respect who decides, and get the paperwork ready
Your parent is the one enrolling, even if you do the research. Present the comparison plainly: the top two or three plans, what each costs for their exact drugs, and what changes from their current plan. Let them make the call, and be ready to help with enrollment itself if they ask.
One piece of paperwork helps: a plan cannot discuss an account with family unless authorization is on file. Help your parent sign CMS-1696, the Appointment of Representative form, and ask the plan if it also needs its own authorization form.
Also note the timing. Annual Enrollment Period runs October 15 through December 7 each year, the window when your parent can switch plans for the following year. Changes take effect January 1 — do the comparison well before December.
The caregiver's plan-choice checklist
Keep this list and reuse it every fall:
- [ ] Complete medicine list, with doses, ready to enter into Plan Finder
- [ ] Total yearly cost compared for at least the top three plans — not premium alone
- [ ] Every drug confirmed on the formulary, with tier and any prior authorization noted
- [ ] Preferred pharmacy confirmed, and mail-order 90-day options checked
- [ ] 2026 cost protections noted: $615 maximum deductible, $2,100 out-of-pocket cap, $35 insulin cap
- [ ] CMS-1696 and any plan authorization form signed and on file
- [ ] Extra Help or a State Pharmaceutical Assistance Program checked if costs are a stretch
- [ ] Enrollment completed before December 7, with a confirmation letter saved
The goal is not a perfect plan — it is the plan that covers their actual medicines at the lowest total cost, at a pharmacy they can use.
Bottom line: Build the medicine list first, compare total yearly cost on Plan Finder, confirm formulary and pharmacy status, and finish before December 7 — that is how a caregiver helps a parent choose the right Part D plan.