The short answer
For medications you take regularly, mail-order pharmacy through your Part D plan can be cheaper than filling monthly at a retail pharmacy — often because plans price a 90-day mail-order supply favorably. But it's not automatic: for some drugs and plans, a 90-day supply at a preferred retail pharmacy is just as cheap, and mail order isn't ideal for drugs you start and stop.
So it's worth checking rather than assuming one is always better.
When mail order saves
Mail order tends to win for stable, long-term maintenance medications — the ones you'll take every month indefinitely. Getting a 90-day supply by mail can lower your per-month cost and save trips to the pharmacy. Many plans specifically encourage mail order for maintenance drugs with better pricing.
It works less well for new prescriptions you're still adjusting, drugs with short courses, or anything you might change soon, since you'd be stuck with a 90-day supply. Our guide to choosing a Part D plan covers how pharmacy options factor into total cost.
How to decide
Compare your plan's cost for a 90-day mail-order supply against a 90-day supply at a preferred retail pharmacy for each maintenance drug. Use mail order where it's cheaper and convenient, and keep short-term or changing medications at a local pharmacy.
The right mix can lower your yearly drug costs without any change in the medications themselves. Our doctor and drug coverage tool helps you compare pharmacy pricing on your plan.
Frequently Asked Questions
Is mail-order pharmacy cheaper on Medicare Part D?
Often for maintenance medications, yes — plans frequently price a 90-day mail-order supply favorably. But for some drugs, a 90-day supply at a preferred retail pharmacy is just as cheap, so compare.
When should I not use mail order?
For new prescriptions you're still adjusting, short courses, or drugs you might change soon, since you'd be committed to a 90-day supply.
How do I know which is cheaper?
Compare your plan's 90-day mail-order price against a 90-day supply at a preferred retail pharmacy for each maintenance drug, then use whichever is cheaper and convenient.
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