Pharmacy Receipt Doesn't Match Part D EOB

What This Means

You picked up a prescription at the pharmacy and paid a certain amount. But when you got your Part D Explanation of Benefits (EOB) in the mail or online, the amount listed as “your cost” was different from what you actually paid. This is confusing — and it matters, because the wrong amount can affect how much credit you get toward your annual out-of-pocket cap.

The good news is that this kind of discrepancy is usually a billing issue, not a coverage denial. In most cases, a phone call to your Part D plan or pharmacy can clear it up. If you overpaid, you are entitled to a refund.

It is important to sort this out, though. Under the Inflation Reduction Act, Part D plans now have a $2,000 annual out-of-pocket cap. Every dollar you pay at the pharmacy should count toward that limit — but only if the claim was processed correctly through your Part D benefit.

Why This Happens

• The pharmacy used a different price than your plan’s negotiated rate. Pharmacies sometimes charge a “usual and customary” price at the register that differs from the lower rate your Part D plan negotiated. The plan later adjusts the claim to reflect the correct amount.
• Your plan retroactively adjusted the claim after the point of sale. Part D plans can change the pricing on a claim days or weeks after you filled the prescription. When this happens, your EOB will show a different cost than what you paid at the counter.
• A discount card was used instead of your Part D benefit. If the pharmacy ran your prescription through a discount card (like GoodRx or a manufacturer coupon) instead of your Part D plan, the price you paid may be lower — but none of that payment counts toward your annual out-of-pocket cap.
• The pharmacy applied the wrong cost-sharing tier. Part D plans organize drugs into tiers (generic, preferred brand, non-preferred, specialty). If the pharmacy billed at the wrong tier, your copay or coinsurance amount will be wrong.
• A coverage gap or catastrophic phase kicked in. Your cost-sharing changes as you move through different phases of Part D coverage during the year. If the pharmacy’s system wasn’t updated or the timing was off, you may have been charged based on the wrong phase.

Should You Appeal?

What To Do Next

1. Gather your documents. Find your pharmacy receipt and your Part D EOB for the same prescription fill. Look for the fill date, drug name, and the amount listed as “patient pay” or “your cost” on each document.
2. Compare the two amounts. If the receipt shows you paid more than the EOB says you should have, you are likely owed a refund. If the receipt shows you paid less, your plan may send you a bill for the difference — but check that the EOB amount is correct first.
3. Call your Part D plan. The phone number is on the back of your plan membership card or on the EOB itself. Tell them the amounts don’t match and ask them to explain the difference. If you overpaid, ask for a refund or a corrected claim.
4. Ask the pharmacy to reprocess if needed. If the pharmacy used a discount card instead of your Part D plan, ask them to reverse the transaction and reprocess it through your Part D benefit. This way the payment will count toward your $2,000 annual out-of-pocket cap.
5. File a grievance if the problem isn’t resolved. If your plan or pharmacy won’t fix the discrepancy, you can file a formal grievance with your Part D plan. Your plan must acknowledge it within 5 days and resolve it within 30 days (or 24 hours for urgent situations).
6. Get free help. Contact your State Health Insurance Assistance Program (SHIP) for one-on-one counseling, or call 1-800-MEDICARE (1-800-633-4227). You can also visit Medicare.gov to look up your plan’s grievance process.

Sources

• Medicare.gov: Part D Grievances, Coverage Determinations, and Appeals — how to file a grievance or appeal with your Part D plan
• CMS: Part D Grievances — official CMS guidance on the grievance process and timelines
• Medicare.gov: Costs in the Coverage Gap — how your costs change as you move through Part D phases
• CMS: Medicare Prescription Payment Plan — information on spreading out-of-pocket drug costs into monthly payments

Frequently Asked Questions