What Changed in the CMS-855B Medicare Enrollment Application?
As of August 3, 2026, CMS requires all clinics and group practices to use the revised CMS-855B when enrolling in Medicare, revalidating, or updating enrollment information. The updated form allows group practices to submit reassignment of benefits directly on the 855B instead of filing a separate CMS-855R, and it removes outdated references to physician assistant employer relationships. Medicare Administrative Contractors will reject any submission using the old version of the form.
Reassignment consolidated: Group practices can now add, change, or terminate provider reassignments in section 4H of the 855B without filing a separate 855R form.
Old form rejected: MACs stopped accepting the previous version on August 3, 2026. Submitting the old form will delay or reject your enrollment action.
PECOS updated: The Internet-based Provider Enrollment, Chain, and Ownership System was updated to mirror the revised paper application, so both paths now reflect the same fields.
What CMS Changed in the 855B
CMS released the revised CMS-855B enrollment application in April 2026, with Medicare Administrative Contractors accepting both old and new versions through August 2, 2026. As of August 3, only the revised form is accepted. The revision number on the current form is dated April 29, 2026, under OMB number 0938-1377.
The most significant change is the addition of section 4H, which allows group practices to report reassignment of benefits directly on the 855B. Previously, every reassignment action required a separate CMS-855R form, meaning a family medicine group adding a new physician had to file two separate applications: the 855I for the individual provider and the 855R for the reassignment. Under the revised 855B, the group can include the reassignment information on its own application, along with the individual practitioner’s signature in section 15E.
CMS also removed references to the physician assistant employer relationship from the application, reflecting current Medicare enrollment rules. The $750 enrollment application fee for 2026, which applies to initial enrollments, re-enrollments, and revalidations for institutional providers and some suppliers, remains unchanged. Individual physicians and non-physician practitioners using the 855I are not subject to this fee.
Does This Affect Family Medicine Group Practices?
Yes. Every family medicine group practice that bills Medicare as a group is affected. The 855B is the enrollment application for clinics and group practices, so any practice that enrolls a new provider, revalidates its Medicare enrollment, changes its practice location, or updates reassignment information must now use the revised form. Solo practitioners who bill under their individual NPI use the 855I instead and are not directly affected by this specific form revision.
In our experience matching family medicine practices with billing partners, enrollment and revalidation delays are among the most common sources of billing disruption. A rejected enrollment form means the new provider cannot bill Medicare until the correct application is accepted and processed, which can take 60 to 90 days from the MAC. Providers often come to us after a new hire has been seeing patients for weeks without a completed enrollment, and the practice discovers it cannot bill for any of those services retroactively.
855B vs. 855I vs. 855R: Which Form Does Your Practice Need?
Medicare enrollment uses different forms for different provider types and actions. The table below shows which form applies to common family medicine enrollment scenarios.
| Scenario | Form required | What changed in 2026 |
|---|---|---|
| Group practice initial enrollment | CMS-855B (revised) | Must use revised version; old form rejected after August 2 |
| Individual provider enrollment | CMS-855I | 855R discontinued; reassignment reported on 855I or 855B |
| Reassignment of benefits | CMS-855B section 4H (group) or 855I (individual) | 855R eliminated; reassignment now consolidated |
| Revalidation | Same form used for initial enrollment | Use revised 855B for groups; PECOS mirrors the update |
| Practice location change | CMS-855B (revised) | Submit change on the revised form only |
For practices that handle enrollment through PECOS rather than paper, the online system was updated to mirror the revised 855B fields. If you use PECOS, confirm that your enrollment record reflects the current structure, particularly if you have pending reassignment actions.
Enrollment and revalidation errors are one of the fastest ways to stop Medicare revenue cold. If your practice does not have staff dedicated to tracking CMS form changes and MAC submission requirements, a billing partner who handles enrollment alongside claims can prevent the gap. Get matched with vetted family medicine billing companies, free.
What Should Your Practice Do Now?
The deadline has already passed, so the action items are about confirming compliance and updating workflows rather than racing to meet a date.
Confirm you are using the revised form. If your practice submits paper 855B applications, verify that your office has the April 2026 revision. Submissions on the old version will be returned unprocessed.
Check PECOS for pending reassignment actions. Log into PECOS and confirm that any pending or recently submitted reassignment changes reflect the current system structure. If you started a reassignment on the old 855R before August 3, confirm with your MAC whether it was processed.
Update your enrollment checklist for new hires. If your onboarding process includes a paper 855R for reassignment, replace that step with the 855B section 4H submission or the PECOS equivalent.
Verify revalidation deadlines. CMS requires periodic revalidation of enrollment. If your next revalidation is approaching, use the revised 855B. Submitting the old version will delay the revalidation and could trigger a hold on claims.
Brief your credentialing staff or partner. Anyone who handles Medicare enrollment for your practice needs to know the 855R is gone and that reassignment now lives on the 855B. One question we hear constantly from practice managers is why enrollment takes so long, and using an outdated form is one of the most avoidable causes.
Common Mistakes on the Revised 855B
Across the billing companies we vet, the same enrollment errors repeat every time CMS revises an application form.
Submitting the old version. The MAC will return it unprocessed. The practice loses weeks, and the provider cannot bill Medicare during the delay.
Filing a separate 855R for reassignment. The 855R has been discontinued. Reassignment now goes through section 4H of the revised 855B for groups or through the 855I for individual providers.
Missing the individual practitioner signature in 15E. When adding a reassignment on the 855B, the individual provider’s signature in section 15E is now required alongside the group’s authorized official signature. Missing it will reject the submission.
Assuming PECOS auto-updated everything. PECOS mirrors the new form structure, but if you had pending applications or changes in progress when the system updated, those may need to be resubmitted or verified.
In-House Enrollment vs. a Billing Partner
Medicare enrollment is detail work that most family medicine practices handle only a few times a year, usually when a provider joins or leaves the group. Because it is infrequent, in-house staff often use outdated forms, miss signature requirements, or submit to the wrong MAC. A billing partner that handles enrollment as part of the revenue cycle catches these issues before submission, because enrollment accuracy is what keeps every subsequent claim payable. For practices that want to understand how a billing partner fits into the broader workflow, our guide on finding the right family medicine billing service covers what to evaluate.
Frequently Asked Questions
Can I still use the old CMS-855B?
No. Medicare Administrative Contractors stopped accepting the previous version on August 2, 2026. All submissions after that date must use the revised form dated April 29, 2026. Using the old form will result in the application being returned unprocessed.
Do I still need to file a separate 855R for reassignment?
No. The CMS-855R has been discontinued. Group practices now report reassignment of benefits in section 4H of the revised CMS-855B, and individual providers can include reassignment information on the CMS-855I.
Does this affect PECOS users?
Yes. PECOS was updated to mirror the revised 855B form structure. If you enroll through PECOS, the system reflects the new fields, but you should verify any pending actions started before the update to confirm they processed correctly.
Is there a fee for submitting the revised 855B?
The 2026 Medicare enrollment application fee is $750 for institutional providers and certain suppliers enrolling, re-enrolling, or revalidating. Individual physicians and non-physician practitioners using the 855I are generally not subject to this fee.
What happens if my 855B submission is rejected?
The provider or group cannot bill Medicare until a valid enrollment is processed. Processing times vary by MAC but typically run 60 to 90 days. A rejected form means restarting from the beginning, which can leave a new provider unable to bill for months.
Does this change affect solo family medicine practitioners?
Solo practitioners who bill under their individual NPI enroll with the CMS-855I, not the 855B. The 855B revision primarily affects group practices. However, the discontinuation of the 855R means solo practitioners also report reassignment information on the 855I rather than a separate form.
Next Steps
Need to understand E/M coding for the providers you are enrolling? See our guide on CPT 99213 documentation and billing for the most common established patient visit code in family medicine.
Verify your PECOS enrollment record now to confirm all reassignments and practice locations are current under the revised form structure.
Ready to hand enrollment and billing off? Get matched with a family medicine billing company that handles enrollment, revalidation, and claims together so nothing falls through the gap.
Medicare enrollment errors stop revenue before a single claim gets submitted. Whether you need a billing partner who handles 855B enrollment alongside daily claims or want to audit your current enrollment status, Family Med Billers connects you with vetted partners at no cost. More than 2,000 providers matched, all 50 states, rates from 6 percent. Matching is 100 percent free.
