Medicare Part D: Your Simple Guide to Prescription Drug Coverage

If you’re on Medicare and need help paying for medicines, Medicare Part D is the part that covers prescriptions. It’s not a free perk – you’ll pick a private plan, pay a monthly premium, and maybe a small deductible. The good news? Most plans cover the drugs your doctor prescribes, and they limit how much you spend each year.

How Medicare Part D Works

When you enroll, you choose a “stand‑alone” prescription drug plan (PDP) or a Medicare Advantage plan that includes drug coverage (MA‑D). Each plan has its own list of covered drugs, called a formulary. Check the formulary before you sign up – if your medication isn’t on it, you’ll pay more out of pocket.

The cost structure usually looks like this: a monthly premium, an annual deductible (often $0‑$445 in 2025), then a co‑pay or coinsurance for each fill. After you and the plan together spend a set amount (the “donut hole”), you enter the coverage gap where you pay a higher share until you hit the catastrophic limit.

Choosing the Right Plan

Start by listing every prescription you take, including dosage and frequency. Use that list to compare plans on three things: monthly premium, total out‑of‑pocket costs for your drugs, and pharmacy network. Some plans let you use mail‑order services for a cheaper price; others require you to stick with local brick‑and‑mortar pharmacies.

Don’t forget extra benefits. Many PDPs offer wellness programs, free flu shots, or discounts on over‑the‑counter items. If you travel often, look for plans that cover prescriptions in multiple states.

Enrollment periods matter. The Annual Election Period runs from October 15 to December 7 each year – that’s the time to switch or join a new plan. You can also enroll during the Initial Enrollment Period (the first 7 months after you turn 65) or if you qualify for a Special Enrollment Period due to loss of other coverage.

Finally, keep an eye on your plan each year. Formularies and costs change, so a plan that was perfect last year might not be the best choice now. Log into Medicare.gov, run a quick comparison, and adjust before the deadline.