Your O&P order is in prior authorization. Here is what you can actually do while it is pending.

The supplier calls. The device you need is on Medicare’s Required Prior Authorization list — or your Medicare Advantage plan flagged it — which means the paperwork has to go to the right place and come back approved before anything ships. You are now in a waiting period.

This guide is about that stretch of time. Not what happens if the authorization comes back as a denial — that guide exists — but the earlier, murkier part, where you are just waiting and want to know whether there is anything to do.

There are a few things. They are mostly about making sure other people have what they need and knowing when to ask a different question.

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What “in prior authorization” means at your level

When your supplier says your device is in prior auth, they are telling you that they have submitted — or are preparing to submit — a formal documentation package to your Medicare Administrative Contractor (MAC). The MAC is the regional entity that administers Medicare claims on CMS’s behalf. It reviews the submission and issues either an affirmative decision (the device is approved for delivery) or a non-affirmative decision (the submitted documentation was insufficient to approve it).

The supplier cannot deliver the device and bill Medicare until they receive an affirmative decision. This is not a technicality they can work around. It is a sequencing requirement: authorization before delivery. If the device arrives at your door before the approval comes through, the claim will not be paid.

What does the MAC actually review? Whether the documentation supports the medical necessity of the specific device under the relevant coverage criteria — primarily the applicable Local Coverage Determination and policy article. That means your prescribing physician’s notes from the face-to-face examination, the written order, any functional assessment documentation, and the supplier’s own clinical rationale for the specific components requested.

You are not party to most of this. The submission happens between your supplier and the MAC. But several of the weak points in the process sit adjacent to you.

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The first useful thing: your physician’s office

The single most common cause of prior authorization delays has nothing to do with the MAC’s review pace. It is the documentation that has to come from your prescribing physician before the supplier can even submit.

For Medicare prior authorization on most prosthetic and orthotic items, the package typically needs to include:

• A written order that specifies the device, is signed, and is dated within the required timeframe
• Documentation of a face-to-face examination between you and the treating practitioner, showing that the exam occurred and supports the medical necessity of the requested device
• Supporting medical records that establish the underlying diagnosis

The supplier is responsible for assembling this and sending it to the MAC. But the physician’s office is often where the bottleneck lives — because they are tracking dozens of patients and the records request from the supplier arrived in an administrative queue.

What you can do: Contact your prescribing physician’s office and let them know that a prior authorization submission is pending and that the supplier needs their documentation. Ask what the expected turnaround is on records releases. If you have a patient portal, you can sometimes see what requests have come in. What you are trying to do is confirm the request did not get lost and identify whether someone needs to prioritize it.

This is not about pressuring your physician’s staff. It is about making sure a request that left the supplier reached the right inbox and has a realistic timeline attached to it. A polite call that says “I know a records request came over for my prior authorization — can you tell me where that stands?” is a reasonable ask.

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What the timeline actually looks like

For items covered under the CMS DMEPOS Prior Authorization program, MACs are generally expected to issue a decision within a defined review window. In practice, standard reviews have run between five and ten business days from the date the MAC receives a complete submission. “Complete” is the operative word: a submission with missing documentation does not start the clock the same way a complete one does.

Business days, not calendar days. If your submission lands on a Thursday before a federal holiday weekend, factor that in.

For Medicare Advantage prior authorization, timelines are set by the individual plan, not CMS. Your plan’s Evidence of Coverage document, or a call to the plan’s provider services line, is where that answer lives. Medicare Advantage plans are required to issue decisions on standard prior auth requests within 72 hours (for urgent situations) or 14 calendar days (for standard requests). Actual practice varies.

The thing to understand about these timelines is that they begin when the MAC or plan receives a complete and reviewable submission — not when the supplier sends it, and not when you first asked about the device. If a submission goes in with missing documentation and the MAC sends it back, that round trip costs days.

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The expedited pathway — when it exists and when to ask about it

For the CMS DMEPOS Prior Authorization program, there is an expedited review pathway. Your supplier requests it by indicating that waiting for the standard timeframe would seriously jeopardize your health or your ability to regain maximum function.

This pathway exists for genuinely urgent situations: a recent discharge from an acute care setting where delay would compromise recovery, a documented deterioration in function or skin integrity tied to a missing device, situations where the clinical picture materially worsens with each week of waiting.

If your situation is urgent in one of these ways — and “urgent” here has a clinical meaning that your prescribing physician can speak to — the question to raise with your supplier is whether they intend to request expedited review and what documentation from your physician would support that request. The expedited pathway is not a blanket workaround for frustration with standard review timelines. It exists because some cases genuinely can’t wait ten business days, and it requires the clinical record to make that case.

Ask your supplier: “Is an expedited review something you can request here, and if so, what does my physician need to document to support it?” That is the question to ask, not the question to answer yourself.

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What to ask your supplier — and how often

Your supplier’s billing coordinator is the person tracking the status of your prior authorization submission. This is a reasonable person to call periodically, but “periodically” does not mean daily. Checking in once every few business days after submission is reasonable. More than that is unlikely to surface new information and creates friction with the people doing the work.

What is actually useful to ask:

• “Has the submission been sent to the MAC?” (If not, when is it expected to go?)
• “Did the MAC receive it and confirm it’s under review?” (Some MACs send acknowledgment; some suppliers track this routinely)
• “Are there any outstanding documentation requests from the MAC?” (If the MAC asks for additional information, the clock is partly on the supplier and the physician’s office to respond)
• “If there’s a missing documentation issue, what is it and who needs to provide it?”

What you are listening for is whether the submission is complete and actively under review, or whether it is stalled waiting for something. If it is stalled, ask who holds the next step.

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What you cannot hurry

The MAC review itself. Once a complete submission is in, the decision is in their queue. Calling the MAC directly as a beneficiary is possible but rarely affects the timeline — the review is a documentation determination, not a customer service issue.

The prior authorization decision is also not a care conversation. The MAC is reviewing a paperwork record. They are not talking to your physician, they are not assessing your function, and they do not have context that isn’t in the submitted documents. If the clinical picture that supports your need for this device is not fully captured in the written record, the documentation is the place where that gets fixed — not a phone call.

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A note on the current moment

CMS added more O&P codes to the Required Prior Authorization, Required Face-to-Face, and Written Order Prior to Delivery lists in August 2026. If your device was not on these lists the last time you ordered a similar item, your current order may require steps that your previous one did not.

Our colleague Eli Park covered what each of those lists actually does and how they interact: “CMS just added more O&P codes to its prior authorization and face-to-face lists”. If you are encountering prior authorization for the first time and want to understand the mechanics before calling your supplier, that piece covers the underlying structure.

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If the situation is genuinely urgent and you cannot wait

If your clinical situation is an emergency — you need a device or a repair immediately, delay creates a real health risk, you are in a post-acute setting with a discharge timeline — the standard prior authorization process may not be the right track at all. Talk to your care team about whether a different ordering pathway or clinical setting changes what’s available to you. Your prescribing physician and the care coordinator at your facility are the right people for that conversation.

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What this guide does not cover

A prior authorization denial, or a non-affirmative decision. If the authorization comes back as a non-affirmative, that is a different situation — there is an appeals process, specific timelines, and defined documentation remedies. That guide is here: Medicare said no to your prosthesis: a plain-language map through the appeals process.

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Amputee News does not provide individualized medical, legal, insurance, or device-fitting advice. Prior authorization processes, timelines, and documentation requirements vary based on your specific coverage, device, and MAC jurisdiction. For guidance specific to your situation, work with your O&P supplier’s billing coordinator, your prescribing physician, and your insurer or Medicare Administrative Contractor.