Medicare is the federal health insurance program for people who are 65 or older, certain younger people with disabilities, and people with End-Stage Renal Disease (permanent kidney failure requiring dialysis or a transplant, sometimes called ESRD).

Medicare Part A (Hospital Insurance)

Part A covers inpatient Hospital, skilled nursing facility, hospice care, and some home health care.

Medicare Part B (Medical Insurance)

Part B covers Professional services, such as outpatient services, medical supplies and Preventive services.

Medicare Part C (Medicare Advantage Plans)

Health Plan offered by a Private company that contracts with Medicare.  Medicare Advantage Plans include HMO’s, PPO’s, Private Fee-for-Service Plans.  Most Medicare services are covered through the plan and aren’t paid for under Original Medicare. Most Medicare Advantage Plans offer prescription drug coverage.

Medicare Part D (prescription drug coverage)

Part D is for drug coverage. 

Medicare Part O (Ordering and Referring)

PECOS was created to support the process by allowing to electronically submit and manage provider’s Medicare enrollment.

CMS  established Internet-based Provider Enrollment, Chain and Ownership System (PECOS) as an alternative to the paper (CMS-855) enrollment process. Internet-based PECOS allows physicians, non-physician practitioners and provider and supplier organizations to enroll, make changes in their Medicare enrollment, view their Medicare enrollment information on file with Medicare, or check Medicare enrollment status.  For more information about the Internet-based PECOS, please click

What is reassignment?

Reassignment allows UCSF to add our Tax IDs to the provider’s current enrollment for Billing Purposes. Providers may reassign their Medicare benefits to multiple groups.   The reassignment will not affect or change any of the current enrollments.  

Medicare Enrollment Requirements

Medicare requires physicians to complete 855i and 855r applications. The OMAG serves as delegated surrogates and prepares an enrollment application on behalf of providers via PECOS.

How to E-sign

Once the OMAG prepares and completes the enrollment application, an email will be sent to the providers with instructions, PECOS username and a separate email with PECOS password.

For questions, please call a UCSF Health Plan Enrollment Analyst.

Nelly Eck – 415-514-2711

Laly Sacro- 415-514-2664

Application Timeline

Processing time:  

  • Generally, Medicare applications are processed within 4-8 Weeks
  • Approved in PECOS
  • Effective date governed by date provider e-signed PECOS App
  • All new applications will retro back 30 days from the date provider signed enrollment application.

**Although this is the advertised Standard processing time, processing time can be as quick as 1 week.


Pursuant to the Patient Affordable Care Act Medicare requires providers to revalidate their Medicare enrollment information every three to five years. 

  • Cycle 1 Revalidation started in 2015 and is complete.
  • Cycle 2 Revalidation started February 2016 and we are still in cycle 2.

CMS posts a list of providers that are due for revalidation.  The list of provider will have a due date or “TBD” which means that CMS has not set a date yet.

  Providers the have opted out of Medicare or are only enrolled to refer and prescribe do not need to revalidate.