Part D plans have networks of pharmacies that agree to work with them. The same prescription can cost different amounts at two pharmacies in the same plan, and the plan may not pay outside its network.

Preferred and Standard Pharmacies

Both are in-network, but you may pay less at preferred pharmacies. For example, the same covered 30-day prescription might have a hypothetical $5 copayment at a preferred pharmacy and $15 at a standard in-network pharmacy. Those example amounts are not a quote; check your plan, drug, quantity, and whether you have met your deductible.

Preferred status depends on your specific plan. A pharmacy that is preferred for one plan may be standard or out-of-network for another.

Mail-Order and Specialty Pharmacies

Plans may offer mail-order prescriptions for medicines you take regularly, sometimes in 90-day supplies. Some medications with special handling or distribution requirements may need to come from a designated specialty pharmacy.

Compare prices rather than assuming mail order is always cheaper.

Out-of-Network Pharmacies

Part D generally expects you to use an in-network pharmacy. Out-of-network coverage is limited to specific circumstances. You may need to pay the full price and ask the plan to pay you back, and some costs may remain your responsibility.

An urgent need for a covered prescription while travelling where you cannot reasonably get to a network pharmacy may qualify for an out-of-network exception under the plan’s rules. Keep the receipt and ask the plan how to submit the claim; payment is not automatic.

If you use a cash discount instead of your Part D coverage, the purchase generally does not count toward the deductible or drug cap unless it meets the plan’s claim and counting rules. Compare the effect on the whole year, not just today’s receipt.

How to Check a Pharmacy

  • Search the plan's current directory
  • Compare the same prescriptions in Medicare Plan Compare
  • Call the plan before filling an expensive medication
  • Confirm whether the pharmacy is preferred or standard
  • Recheck each plan year

Medicare's pharmacy guidance explains each category.

Before an expensive fill, have the plan compare the same drug, strength, quantity, and supply length at your available pharmacies. For the full premium-plus-prescription calculation, use the Part D comparison example.

Medicare policy sources last checked: October 8, 2026.