Few things are more frustrating for a practice owner than learning that a Medicare application you submitted has been rejected and you need to start again. Most rejections are not about whether you qualify. They come down to missing information, missed requests and records that do not line up, which means most of them are preventable.
This guide explains what a rejection actually is, how it differs from a denial, and the reasons we see most often.
Rejection is not the same as denial
Medicare uses these two words for very different outcomes, and the difference matters for what you do next.
- A rejection is procedural. Under 42 CFR 424.525, CMS may reject an enrollment application when it is incomplete and the missing information or documentation is not furnished in time, or when a required application fee or hardship request is missing. A rejected application has no appeal rights. To enroll, you submit a new, complete application.
- A denial is a decision on the merits under 42 CFR 424.530, for reasons such as not meeting enrollment requirements, certain exclusions or felony convictions, or false or misleading information. Denials come with appeal rights.
Most of the problems practices run into are rejections. That is the good news: they are about process, and process can be fixed.
The 30-day clock
When the Medicare contractor needs more information, it sends a development request to the contact on your application. CMS rules allow the contractor to reject the application if the missing information is not furnished within 30 calendar days of that request. The Program Integrity Manual adds two details that catch people off guard:
- The clock starts when the request is sent, and a follow-up request does not restart it.
- If you send back some but not all of what was requested, the contractor is not required to ask again before rejecting.
The contractor can extend the window when a provider is actively working to resolve the issues, but you should not count on it.
The most common reasons applications are rejected
1. Missed or partial responses to development requests
This is the big one. The request went to an email nobody checks, a former employee, or a provider who was on vacation. Or the response answered three of the four questions.
2. Missing supporting documents
Licenses, certifications, ownership documents, banking documentation and other attachments need to come with the application or follow within the required window. CMS rules allow rejection when required supporting documentation is not furnished within 30 calendar days of submitting the application.
3. Missing application fee or hardship request
Institutional providers and certain suppliers owe an enrollment application fee. If the fee, or a hardship exception request, is not submitted with the application, it can be rejected. Individual practitioners filing a CMS-855I are not charged this fee. Physician and non-physician practitioner groups enrolling on a CMS-855B, and reassignments on the CMS-855R, are also exempt. Our CMS-855 form guide covers which applications it applies to.
4. The wrong form or an outdated version
Filing a group on an individual form, or using a retired version such as the old CMS-855R, gets the application sent back. See our 855R guide for why that form no longer exists.
5. Incomplete reassignment packages
CMS rules specifically allow rejection when the forms needed to process a reassignment package are not submitted within 30 days. Missing signatures from either the practitioner or the group's official are a frequent cause.
6. Information that does not match other records
Names, addresses, license numbers and taxonomies that disagree with NPPES, state licensing boards or IRS records lead to questions. Each question restarts the cycle of request and response, and each one is another chance to miss a deadline.
7. Unsolicited early revalidations
Revalidations submitted more than seven months before the due date, without a notice from CMS, are returned. Our revalidation guide explains the timing rules.
What a rejection really costs you
A rejection resets the process. You assemble and submit a complete new application, and the review starts over. For a practice that has already hired a clinician or opened a location, that means more time providing care that cannot yet be billed to Medicare. That is why we put most of our effort into the file before it is submitted, not after.
How to avoid a rejection
At a high level, the practices that rarely see rejections do three things well:
- They reconcile NPPES, licensing and ownership records before filing.
- They make sure the contact on the application is someone who will see and act on a request quickly.
- They treat every development request as urgent and answer all of it at once.
How Maverick prevents and fixes rejections
We review your records before anything is filed, assemble the supporting documents, confirm the right form and version, and submit once your file is complete. We list ourselves as the contact where appropriate, so development requests come straight to a specialist, and we answer them in full. If you have already been rejected, we find out why, fix the underlying issue and prepare a clean new application. Throughout, we follow up on a set schedule and keep you updated.
See our full Medicare and Medicaid enrollment service, and if you are an individual practitioner, our CMS-855I guide.
Sources: 42 CFR 424.525 (rejection) and 424.530 (denial); 42 CFR 424.514 (application fee); Medicare Program Integrity Manual, Chapter 10, Section 10.4 (CMS Pub. 100-08); CMS, Revalidations (Renewing Your Enrollment). Verified October 2026.