Starting or expanding your O&P DME? Your first Medicare year now runs through prior auth

On October 15, 2026, CMS starts a probationary prior authorization process for newly enrolled DMEPOS suppliers. The list has 38 orthotic codes and 2 bone growth stimulator codes. If you are opening an ortho DME, most of your first-year Medicare volume now goes through a DME MAC review before you can deliver.

What CMS changed

CMS posted the Probationary Prior Authorization Process for newly enrolled suppliers. Here are the facts.

The probation list does not replace the standard Required Prior Authorization List. You must follow both. None of the 40 probation codes are on the standard list, so they add to it. By April 2027, a new ortho supplier needs a PA decision on 61 codes: 40 from the probation list and 21 orthoses from the standard list.

The 40 codes, by body region

Read this list with your launch product plan open. These are the high-volume items most new ortho DMEs start with: walking boots, wrist braces, hinged knee sleeves, and lumbar supports. The full list is in the CMS code list PDF.

How a probationary PA works

CMS uses the steps from the DMEPOS prior authorization operational guide.

1. Collect the documents. For orthoses on the standard list, CMS requires a written order prior to delivery (WOPD), the face-to-face exam, and medical records that support medical necessity. Expect the same for probation codes.
2. Submit the prior authorization request (PAR). Send it to your DME MAC by fax, esMD, or the DME MAC portal.
3. Wait for the decision. The DME MAC decides in 5 business days, and not more than 7 calendar days. If a delay puts the patient's health at risk, the MAC tries to decide in 2 business days.
4. Deliver and bill. An affirmed PAR gets a 14-character unique tracking number (UTN). Put the UTN on the claim in the 2300 loop REF segment (REF01 = G1), or in item 23 on a paper 1500.
5. Fix and resubmit if needed. A non-affirmation letter lists what is missing. You can resubmit as many times as you need. Each resubmission gets the same 5-business-day clock.

The DME MAC automatically denies a claim for a PA code that has no decision and no UTN. An affirmed PAR also does not guarantee payment. The claim can still deny for technical errors or for information the MAC did not have at review.

What this means if you are building an ortho DME

1. Your first claim starts the clock

Probation starts at your first claim for a listed code, not at enrollment. You cannot wait it out. Have the PA workflow running before you bill. Do not build the process during your first month of claims.

2. Same-day dispensing gets harder

Many ortho DMEs grow by fitting patients in the clinic or at discharge. Walking boots, post-op hip abduction orthoses (L1686), and airplane splints (L3960) are often same-day items. Under probation, you need a PA decision before you deliver.

The CMS guide has an ST modifier exception for acute cases. That exception lists only codes on the standard list, not probation codes. Ask your DME MAC how it treats urgent probation items. Do this before you promise same-day fits to referring clinics.

3. Plan cash flow for a slower first year

Every Medicare order on the list gets a PA step before delivery. One clean submission can add up to 7 calendar days. A non-affirmation and resubmission can add a second week. Put that delay into your working capital and inventory model. Tell referral sources the time frame up front.

4. The practitioner's note decides the outcome

The DME MAC reviews the medical record, not your intake form. CMS counts orthotist notes as part of the medical record. But they only help if they support the treating practitioner's notes. If the two do not agree, the MAC can deny.

Build a checklist for each code family from the LCDs:

• Knee Orthoses (L33318)
• Ankle-Foot/Knee-Ankle-Foot Orthoses (L33686)
• Spinal Orthoses: TLSO and LSO (L33790)

Send referring clinics a one-page guide on what their notes must say. This is the cheapest fix you have.

5. Track your affirmation rate from day one

Log every PAR, every decision, and every non-affirmation reason. Review the log each week. Fix patterns at the source: a clinic, a code, or a missing document.

For the standard PA program, CMS exempts suppliers with a 90% affirmation rate on at least 10 requests. Use 90% as your target in the probation year. The habits you build now carry into the standard program.

6. Buying or expanding can trigger it too

The program covers certain changes of ownership. The regulation's definition of a new supplier also includes 100% ownership changes and reactivated enrollments. If you plan to buy an existing DME, raise the probation year in diligence and model it in the deal.

Each DMEPOS location also enrolls in Medicare on its own. If you open a new location, ask your DME MAC if it starts a probation year.

If you already bill Medicare

Established suppliers are not on probation. But the standard list keeps growing:

• L0456, L0457, L0486, and L1833 need prior auth nationwide from October 28, 2026.
• L3761 and L3916 phase in from October 28, 2026, and go nationwide on April 26, 2027.

If you buy another supplier, add a location, or reactivate an enrollment, check if the probation rules apply.

A first-year checklist

• Map your launch products against the 40 probation codes and the 21 standard orthoses codes.
• Set up DME MAC portal and esMD access before your first claim.
• Build a documentation checklist for each code family from the LCDs.
• Give referring clinics a one-page guide for their notes.
• Add a required UTN field to your order and billing workflow.
• Track affirmation rate and non-affirmation reasons each week.
• Ask your DME MAC how it handles urgent items on the probation list.
• Add 7 to 14 days of delivery time to your cash flow model.

Where GenHealth fits

GenHealth is an agentic OS for healthcare. For DME prior auth, it:

• Reads incoming orders and clinical notes from fax and email, and flags missing documents before submission.
• Builds the PA packet and submits it through the right channel, including DME MAC portals such as myCGS and Noridian.
• Checks status, reads non-affirmation letters, and sends the missing items back to intake.
• Logs the UTN to the order in Brightree or Niko Health, so the claim goes out with it.
• Keeps an audit trail of every step.

For a new supplier, that means you can run a year of probationary PA without first building a large PA team. Piedmont Medical Solutions saw a 34.2% increase in paid-to-date collections after switching to GenHealth (Jack Bachman, CEO).

Opening an ortho DME or adding a location? Book a demo and we will map your product list against the probation codes with you.

Sources

• CMS: Probationary Prior Authorization Process for Newly Enrolled Suppliers
• CMS: DMEPOS Probationary Prior Authorization List (updated 9/1/2026)
• CMS: Operational Guide for DMEPOS Prior Authorization (updated 9/2/2026)
• CMS: Required Prior Authorization List (updated 7/29/2026)
• eCFR: 42 CFR §424.527

This post is general information, not legal or billing advice. Confirm details for your situation with your DME MAC.